Grails

https://grails.apache.org/docs/3.3.18/
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### Enum Mapping Setup

Source: https://grails.apache.org/docs/3.3.18/ref/Database%20Mapping/column.html

Example domain setup and enum definition for testing different enum mapping strategies.

```groovy
package demo

import groovy.transform.CompileStatic

@CompileStatic
class BootStrap {

    def init = { servletContext ->
        Book.saveAll(
            new Book(name: 'Grails 3 - Step by Step',
                     status: Status.NOT_SET),
            new Book(name: 'Grails 3 - A practical guide to application development',
                     status: Status.BORROWED),
            new Book(name: 'Falando de Grails',
                     status: Status.SOLD),
        )
    }
    def destroy = { }
}
```

```groovy
package demo

import groovy.transform.CompileStatic

@CompileStatic
enum Status {
    NOT_SET(-1),
    BORROWED(0),
    SOLD(1),

    final int id
    private Status(int id) { this.id = id }
}
```

--------------------------------

### Create Controller Command Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-controller.html

Basic usage examples for generating controllers with or without specified names and packages.

```bash
grails create-controller
grails create-controller Book
grails create-controller org.bookstore.book
```

--------------------------------

### create-unit-test command examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-unit-test.html

Basic usage examples for generating unit tests with or without package specifications.

```bash
grails create-unit-test
grails create-unit-test book
grails create-unit-test org.bookstore.Book
```

--------------------------------

### create-domain-class command usage examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-domain-class.html

Examples of invoking the command with different naming conventions and package structures.

```bash
grails create-domain-class
grails create-domain-class Book
grails create-domain-class org.bookstore.Book
```

--------------------------------

### Handle Setup Persistence in Integration Tests

Source: https://grails.apache.org/docs/3.3.18/guide/testing.html

Demonstrates how data persisted in setup() is not rolled back, requiring manual cleanup or alternative strategies.

```groovy
import grails.testing.mixin.integration.Integration
import grails.gorm.transactions.*
import spock.lang.*

@Integration
@Rollback
class BookSpec extends Specification {

    void setup() {
        // Below line would persist and not roll back
        new Book(name: 'Grails in Action').save(flush: true)
    }

    void "test something"() {
        expect:
        Book.count() == 1
    }
}
```

--------------------------------

### Create Interceptor Command Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-interceptor.html

Basic usage examples for generating interceptors with or without specified names and packages.

```bash
grails create-interceptor
grails create-interceptor Book
grails create-interceptor org.bookstore.book
```

--------------------------------

### Create Integration Test Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-integration-test.html

Basic usage examples for generating integration tests with or without specific class names and packages.

```bash
grails create-integration-test
grails create-integration-test book
grails create-integration-test org.bookstore.Book
```

--------------------------------

### Install and Create Applications with Profiles

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Commands for installing a profile locally and creating new applications using specific profile identifiers.

```bash
$ gradle install
```

```bash
$ grails create-app myapp --profile mycompany
```

```bash
$ grails create-app myapp --profile com.mycompany:mycompany:1.0.1
```

--------------------------------

### Build Grails Installation

Source: https://grails.apache.org/docs/3.3.18/guide/contributing.html

Create a local GRAILS_HOME installation from the project root.

```bash
./gradlew install
```

--------------------------------

### List available plugins

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/list-plugins.html

Basic command to list all installable plugins.

```bash
grails list-plugins
```

--------------------------------

### Example feature.yml configuration

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

A concrete example of a feature configuration defining build plugins and dependencies.

```yaml
description: Adds Asset Pipeline to a Grails project
build:
    plugins:
        - asset-pipeline
dependencies:
    build:
        - 'com.bertramlabs.plugins:asset-pipeline-gradle:2.5.0'
    runtime:
        - "org.grails.plugins:asset-pipeline"
```

--------------------------------

### Create functional test command examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-functional-test.html

Basic usage examples for generating functional tests with or without specific names and packages.

```bash
grails create-functional-test
grails create-functional-test book
grails create-functional-test org.bookstore.Book
```

--------------------------------

### Auto-wire a Bean into a Controller (Partial)

Source: https://grails.apache.org/docs/3.3.18/guide/spring.html

Example showing the start of a controller class for auto-wiring beans defined in XML.

```groovy
class ExampleController {
```

--------------------------------

### Install and Use a Local Plugin

Source: https://grails.apache.org/docs/3.3.18/guide/plugins.html

Commands to install a plugin to the local Maven cache and declare it as a dependency in build.gradle.

```bash
grails install
```

```groovy
compile "org.grails.plugins:quartz:0.1"
```

--------------------------------

### Quartz Plugin Metadata Example

Source: https://grails.apache.org/docs/3.3.18/guide/plugins.html

A comprehensive example of a plugin descriptor class defining metadata and configuration properties.

```groovy
package quartz

@Slf4j
class QuartzGrailsPlugin extends Plugin {
    // the version or versions of Grails the plugin is designed for
    def grailsVersion = "3.0.0.BUILD-SNAPSHOT > *"
    // resources that are excluded from plugin packaging
    def pluginExcludes = [
            "grails-app/views/error.gsp"
    ]
    def title = "Quartz" // Headline display name of the plugin
    def author = "Jeff Brown"
    def authorEmail = "zzz@yyy.com"
    def description = '''\
Adds Quartz job scheduling features
'''
    def profiles = ['web']
    List loadAfter = ['hibernate3', 'hibernate4', 'hibernate5', 'services']
    def documentation = "http://grails.org/plugin/quartz"
    def license = "APACHE"
    def issueManagement = [ system: "Github Issues", url: "http://github.com/grails3-plugins/quartz/issues" ]
    def developers = [
            [ name: "Joe Dev", email: "joedev@gmail.com" ]
    ]
    def scm = [ url: "https://github.com/grails3-plugins/quartz/" ]

    Closure doWithSpring()......
```

--------------------------------

### publishGuide()

Source: https://grails.apache.org/docs/3.3.18/api/grails/doc/gradle/PublishGuide.html

Executes the generation of the gdoc-based HTML user guide.

```APIDOC
## publishGuide()

### Description
Executes the task to generate a gdoc-based HTML user guide based on the configured properties.

### Return Type
java.lang.Object
```

--------------------------------

### Verify Grails installation

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Check the installed Grails version to confirm successful setup.

```text
Grails version: 3.3.18
```

--------------------------------

### Setup Multi-Project Build

Source: https://grails.apache.org/docs/3.3.18/guide/plugins.html

Commands and configuration files for setting up an application and plugin in a multi-project build environment.

```bash
$ grails create-app myapp
$ grails create-plugin myplugin
```

```groovy
include "myapp", "myplugin"
```

--------------------------------

### Example output of list-plugins

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/list-plugins.html

Typical output format when running the list-plugins command.

```text
| Available Plugins
* asset-pipeline
* cache
* cache-ehcache
* fields
* geb
* hibernate
* mongodb
* quartz
* scaffolding
```

--------------------------------

### Setup Inline Plugins

Source: https://grails.apache.org/docs/3.3.18/guide/plugins.html

Commands and configuration to set up a multi-project build for inline plugin development.

```bash
$ grails create-app myapp
$ grails create-plugin myplugin
```

```groovy
include 'myapp', 'myplugin'
```

```groovy
compile project(':myplugin')
```

--------------------------------

### GORM find Method Usage Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/find.html

Demonstrates various ways to use the find method including HQL with parameters, query caching, query by example, and where criteria.

```groovy
// Dan brown's first book
Book.find("from Book as b where b.author='Dan Brown'")

// with a positional parameter
Book.find("from Book as b where b.author=?", ['Dan Brown'])

// with a named parameter
Book.find("from Book as b where b.author=:author", [author: 'Dan Brown'])

// use the query cache
Book.find("from Book as b where b.author='Dan Brown'", [cache: true])
Book.find("from Book as b where b.author=:author",
          [author: 'Dan Brown'],
          [cache: true])

// query by example
def example = new Book(author: "Dan Brown")
Book.find(example)

// Using where criteria (since Grails 2.0)
Person p = Person.find { firstName == "Bart" }
```

--------------------------------

### Example Request URL

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

A sample URL demonstrating how request parameters are passed to the save action.

```text
/book/save?title=The%20Stand&author=Stephen%20King
```

--------------------------------

### Run a Grails application

Source: https://grails.apache.org/docs/3.3.18/guide/commandLine.html

Standard command to start a Grails application.

```bash
grails run-app
```

--------------------------------

### Basic script implementation

Source: https://grails.apache.org/docs/3.3.18/guide/commandLine.html

A simple script example that defines a description and prints output to the console.

```groovy
description "Example description", "grails hello-world"

println "Hello World"
```

--------------------------------

### findAll Pagination and Caching

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/findAll.html

Examples showing how to apply pagination and 2nd level cache settings to HQL queries.

```Groovy
Book.findAll("from Book as b where b.author=:author",
             [author: 'Dan Brown'], [max: 10, offset: 5])
```

```Groovy
Book.findAll("from Book as b where b.author=:author",
             [author:'Dan Brown'], [max: 10, offset: 5, cache: true])
```

--------------------------------

### waitForStartup

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/cli/profile/commands/io/ServerInteraction.html

Blocks execution until the server at the specified host and port has started.

```APIDOC
## void waitForStartup(String host, int port)

### Description
Waits for the server to startup at the specified host and port.

### Parameters
- **host** (String) - Optional (default: "localhost") - The host address.
- **port** (int) - Optional (default: 8080) - The port number.
```

--------------------------------

### Example profile.yml configuration

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Defines default features, build plugins, and dependencies for the custom profile.

```yaml
features:
    defaults:
        - hibernate
        - asset-pipeline
build:
    plugins:
        - org.grails.grails-web
    excludes:
        - org.grails.grails-core
dependencies:
    compile:
        - "org.mycompany:myplugin:1.0.1"
```

--------------------------------

### Print Hello World in a Grails script

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

A basic example of printing output from a Grails script.

```Groovy
println "Hello World"
```

--------------------------------

### publish()

Source: https://grails.apache.org/docs/3.3.18/api/grails/doc/gradle/PublishPdf.html

Executes the PDF generation process for the user guide.

```APIDOC
## publish()

### Description
Executes the task to generate a PDF user guide based on gdoc files. This method assumes that the single-page HTML user guide has already been created in the default location.

### Return Type
java.lang.Object
```

--------------------------------

### Define Hello World controller action

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Example implementation of a controller action that renders a string to the browser.

```groovy
package helloworld

class HelloController {

    def index() {
        render "Hello World!"
    }
}
```

--------------------------------

### UrlValidator Usage Examples

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/validation/routines/UrlValidator.html

Demonstrates how to instantiate and use UrlValidator with specific schemes versus default settings.

```java
    String[] schemes = {"http","https"}.
    UrlValidator urlValidator = new UrlValidator(schemes);
    if (urlValidator.isValid("ftp://foo.bar.com/")) {
       System.out.println("url is valid");
    } else {
       System.out.println("url is invalid");
    }
```

```java
    UrlValidator urlValidator = new UrlValidator();
    if (urlValidator.isValid("ftp://foo.bar.com/")) {
       System.out.println("url is valid");
    } else {
       System.out.println("url is invalid");
    }
```

--------------------------------

### Display Profile Information

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/profile-info.html

Examples of using the profile-info command with different identifier formats.

```bash
grails profile-info rest-api
grails profile-info org.grails.profiles:rest-api
grails profile-info org.grails.profiles:rest-api:3.1.0
```

--------------------------------

### Example JSON Output

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

The resulting JSON output from rendering a domain instance.

```json
{id:1, title:"The Stand"}
```

--------------------------------

### findAll HQL and Query by Example usage

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/findAll.html

Demonstrates basic HQL queries, positional and named parameters, pagination, joins, and query-by-example.

```Groovy
// everything
Book.findAll()

// with a positional parameter
Book.findAll("from Book as b where b.author=?", ['Dan Brown'])

// 10 books from Dan Brown staring from 5th book ordered by release date
Book.findAll("from Book as b where b.author=? order by b.releaseDate",
             ['Dan Brown'], [max: 10, offset: 5])

// examples with max/offset usage
def query = "from Book as b where b.author='Dan Brown' order by b.releaseDate"

// first 10 books
Book.findAll(query, [max: 10])

// 10 books starting from 5th
Book.findAll(query, [max: 10, offset: 5])

// examples with named parameters
Book.findAll("from Book as b where b.author=:author",
             [author: 'Dan Brown'])
Book.findAll("from Book as b where b.author=:author",
             [author: 'Dan Brown'], [max: 10, offset: 5])
Book.findAll("from Book as b where b.author in (:authors)",
             [authors: ['Dan Brown', 'Jack London']])

// examples with tables join
Book.findAll("from Book as b where not exists " +
                "(from Borrow as br where br.book = b)")

// query by example
def example = new Book(author: "Dan Brown")
Book.findAll(example)

// Use where criteria (since Grails 2.0)
def results = Person.findAll {
     lastName == "Simpson"
}
def results = Person.findAll(sort:"firstName") {
     lastName == "Simpson"
}
```

--------------------------------

### Example JSON output

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

The resulting JSON structure from the render method example.

```json
[
    {"title":"The Stand"},
    {"title":"Shining"}
]
```

--------------------------------

### Gradle Build Output

Source: https://grails.apache.org/docs/3.3.18/guide/plugins.html

Example output showing plugin sources being compiled and added to the application classpath.

```text
:myplugin:compileAstJava UP-TO-DATE
:myplugin:compileAstGroovy UP-TO-DATE
:myplugin:processAstResources UP-TO-DATE
:myplugin:astClasses UP-TO-DATE
:myplugin:compileJava UP-TO-DATE
:myplugin:configScript UP-TO-DATE
:myplugin:compileGroovy
:myplugin:copyAssets UP-TO-DATE
:myplugin:copyCommands UP-TO-DATE
:myplugin:copyTemplates UP-TO-DATE
:myplugin:processResources
:myapp:compileJava UP-TO-DATE
:myapp:compileGroovy
:myapp:processResources UP-TO-DATE
:myapp:classes
:myapp:findMainClass
:myapp:bootRun
Grails application running at http://localhost:8080 in environment: development
```

--------------------------------

### Configure Multiple DataSources

Source: https://grails.apache.org/docs/3.3.18/guide/services.html

Example configuration for defining primary and secondary data sources.

```YAML
dataSources:
    dataSource:
        pooled: true
        jmxExport: true
        .....
    secondary:
        pooled: true
        jmxExport: true
        .....
```

--------------------------------

### Vnd.Error Response Example

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Example response when the client requests application/vnd.error+json format.

```bash
$ curl -i -H "Accept: application/vnd.error+json,application/json" -H "Content-Type: application/json" -X POST -d "" http://localhost:8080/books
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Content-Type: application/vnd.error+json;charset=ISO-8859-1

[
    {
        "logref": "book.nullable,
        "message": "Property [title] of class [class rest.test.Book] cannot be null",
        "_links": {
            "resource": {
                "href": "http://localhost:8080/rest-test/books"
            }
        }
    }
]
```

--------------------------------

### Example script content

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-script.html

The generated script file structure using the GroovyScriptCommand API.

```groovy
description "Example description", "grails example-usage"

println "Example Script"
```

--------------------------------

### Build with Gradle directly

Source: https://grails.apache.org/docs/3.3.18/guide/commandLine.html

Invoke a local installation of Gradle to perform build tasks.

```bash
$ gradle assemble
```

--------------------------------

### XML Request Body Example

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Example XML structure used as a request body for binding to a Book object.

```xml
<?xml version="1.0" encoding="UTF-8"?>
<book>
    <title>The Stand</title>
    <authorName>Stephen King</authorName>
</book>
```

--------------------------------

### Retrieve First Instance with first()

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/first.html

Examples of using the first() method with and without sorting parameters.

```groovy
// retrieve the first person ordered by the identifier
def p = Person.first()

// retrieve the first person ordered by the lastName property
p = Person.first(sort: 'lastName')

// retrieve the first person ordered by the lastName property
p = Person.first('lastName')
```

--------------------------------

### Launch Grails Console with Environment

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/console.html

Starts the console within a specific Grails environment.

```bash
grails <<environment>>* console
```

--------------------------------

### Create Tag Library Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-taglib.html

Demonstrates various ways to invoke the create-taglib command, including interactive mode and specifying names with or without packages.

```bash
grails create-taglib
grails create-taglib book
grails create-taglib org.bookstore.Book
```

--------------------------------

### Start Grails interactive console

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Navigate to the project directory and launch the interactive Grails shell.

```bash
$ cd helloworld
$ grails
```

--------------------------------

### Install Plugin to Local Maven Repository

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/package-plugin.html

Installs the packaged plugin into the local Maven repository for use in other projects.

```bash
grails install
```

--------------------------------

### Create a New Grails Application

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Initialize a new project directory named helloworld.

```text
grails create-app helloworld
```

--------------------------------

### Test Execution Output Example

Source: https://grails.apache.org/docs/3.3.18/guide/testing.html

Sample console output showing the results of a test run.

```text
-------------------------------------------------------
Running Unit Tests...
Running test FooTests...FAILURE
Unit Tests Completed in 464ms ...
-------------------------------------------------------
```

--------------------------------

### Package and Run Application

Source: https://grails.apache.org/docs/3.3.18/guide/conf.html

Package the application into a WAR file and execute it using java -jar.

```bash
$ grails package
$ java -jar build/libs/myapp-0.1.war
```

--------------------------------

### Example HAL JSON document

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

A sample representation of an orders list using the HAL standard.

```json
{
    "_links": {
        "self": { "href": "/orders" },
        "next": { "href": "/orders?page=2" },
        "find": {
            "href": "/orders{?id}",
            "templated": true
        },
        "admin": [{
            "href": "/admins/2",
            "title": "Fred"
        }, {
            "href": "/admins/5",
            "title": "Kate"
        }]
    },
    "currentlyProcessing": 14,
    "shippedToday": 20,
    "_embedded": {
        "order": [{
            "_links": {
                "self": { "href": "/orders/123" },
                "basket": { "href": "/baskets/98712" },
                "customer": { "href": "/customers/7809" }
            },
            "total": 30.00,
            "currency": "USD",
            "status": "shipped"
        }, {
            "_links": {
                "self": { "href": "/orders/124" },
                "basket": { "href": "/baskets/97213" },
                "customer": { "href": "/customers/12369" }
            },
            "total": 20.00,
            "currency": "USD",
            "status": "processing"
        }]
    }
}
```

--------------------------------

### Install Grails via SDKMAN

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Commands to install the latest or a specific version of Grails using the SDKMAN tool.

```bash
sdk install grails
```

```bash
sdk install grails {version}
```

--------------------------------

### init(String)

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/test/support/GrailsTestRequestEnvironmentInterceptor.html

Establishes a mock request environment.

```APIDOC
## Method: init(String controllerName)

### Description
Establishes a mock request environment for the specified controller.

### Parameters
- **controllerName** (java.lang.String) - Optional - The name of the controller to mock. Defaults to DEFAULT_CONTROLLER_NAME.
```

--------------------------------

### Grails CLI Error Example

Source: https://grails.apache.org/docs/3.3.18/guide/conf.html

Example of an error message triggered when referencing application classes in application.groovy during CLI execution.

```text
Error occurred running Grails CLI:
startup failed:script14738267015581837265078.groovy: 13: unable to resolve class com.foo.Bar
```

--------------------------------

### Create an application using a custom profile

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Uses the custom profile to bootstrap a new application.

```bash
$ grails create-app myapp --profile mycompany
```

```bash
$ grails create-app myapp --profile com.mycompany:mycompany:1.0.1
```

--------------------------------

### Publish profile to local repository

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Installs the profile locally using Gradle to make it available for use.

```bash
$ gradle install
```

--------------------------------

### Usage syntax for create-profile

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-profile.html

The standard command syntax for creating a profile.

```bash
grails create-profile <<name>>
```

--------------------------------

### Configure SSL via command-line

Source: https://grails.apache.org/docs/3.3.18/guide/deployment.html

Alternative method to enable SSL using system properties during application startup.

```bash
-Dserver.ssl.enabled=true -Dserver.ssl.key-store=/path/to/keystore
```

--------------------------------

### Accessing URL Mapping Constraints

Source: https://grails.apache.org/docs/3.3.18/api/grails/web/mapping/UrlMapping.html

Example of a URL pattern that results in multiple ConstrainedProperty instances.

```text
 
     /blog/$author/$title/$year?/$month?/$day?
 
```

--------------------------------

### Run Application with Plugin

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Execute the application and observe the Gradle output to verify plugin sources are on the classpath.

```bash
$ cd myapp
$ grails run-app -verbose
```

```text
:myplugin:compileAstJava UP-TO-DATE
:myplugin:compileAstGroovy UP-TO-DATE
:myplugin:processAstResources UP-TO-DATE
:myplugin:astClasses UP-TO-DATE
:myplugin:compileJava UP-TO-DATE
:myplugin:configScript UP-TO-DATE
:myplugin:compileGroovy
:myplugin:copyAssets UP-TO-DATE
:myplugin:copyCommands UP-TO-DATE
:myplugin:copyTemplates UP-TO-DATE
:myplugin:processResources
:myapp:compileJava UP-TO-DATE
:myapp:compileGroovy
:myapp:processResources UP-TO-DATE
:myapp:classes
:myapp:findMainClass
:myapp:bootRun
Grails application running at http://localhost:8080 in environment: development
```

--------------------------------

### create-service command usage examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-service.html

Demonstrates various ways to invoke the create-service command, including interactive mode and specifying names with or without packages.

```bash
grails create-service
grails create-service book
grails create-service org.bookstore.Book
```

--------------------------------

### GET /books

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Retrieves a list of books.

```APIDOC
## GET /books

### Description
Retrieves a list of all books.

### Method
GET

### Endpoint
/books
```

--------------------------------

### nextValue()

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/web/json/JSONTokener.html

Get the next value from the source.

```APIDOC
## public java.lang.Object nextValue()

### Description
Get the next value. The value can be a Boolean, Double, Integer, JSONArray, JSONObject, Long, or String, or the JSONObject.NULL object.

### Returns
- **Object** - The parsed value.

### Throws
- **JSONException** - If syntax error.
```

--------------------------------

### Usage Examples for generate-all

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/generate-all.html

Demonstrates various ways to invoke the generate-all command, including targeting specific classes or all domain classes.

```bash
grails generate-all
grails generate-all org.bookstore.Book
grails generate-all "*"
```

--------------------------------

### get()

Source: https://grails.apache.org/docs/3.3.18/api/grails/util/Holder.html

Retrieves the object held by the instance.

```APIDOC
## Method: get()

### Description
Retrieves the object currently held by this instance.

### Returns
- **T** - The held object.
```

--------------------------------

### GET /books/{id}

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Retrieves a specific book by its ID.

```APIDOC
## GET /books/{id}

### Description
Retrieves a specific book by its ID.

### Method
GET

### Endpoint
/books/{id}

### Parameters
#### Path Parameters
- **id** (string) - Required - The unique identifier of the book.
```

--------------------------------

### main(String[] args)

Source: https://grails.apache.org/docs/3.3.18/api/grails/ui/script/GrailsApplicationScriptRunner.html

The main entry point to run an existing Application class.

```APIDOC
## static void main(java.lang.String[] args)

### Description
Main method to run an existing Application class.

### Parameters
- **args** (String[]) - Required - Command line arguments.
```

--------------------------------

### Define a Domain Model

Source: https://grails.apache.org/docs/3.3.18/guide/services.html

Example of a domain class with a hasMany relationship.

```Groovy
class Author {
    String name
    Integer age

    static hasMany = [books: Book]
}
```

--------------------------------

### getPluginVersion(Class clazz)

Source: https://grails.apache.org/docs/3.3.18/api/grails/plugins/GrailsVersionUtils.html

Get the version of the plugin for a particular class.

```APIDOC
## static String getPluginVersion(Class clazz)

### Description
Get the version of the plugin for a particular class.
```

--------------------------------

### Execute install-templates command

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/install-templates.html

Run this command to copy Grails generation templates to the project's src/main/templates/scaffolding directory.

```bash
grails install-templates
```

--------------------------------

### getPluginName(Class clazz)

Source: https://grails.apache.org/docs/3.3.18/api/grails/plugins/GrailsVersionUtils.html

Get the name of the plugin for a particular class.

```APIDOC
## static String getPluginName(Class clazz)

### Description
Get the name of the plugin for a particular class.
```

--------------------------------

### Generate Project Documentation

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/docs.html

Execute the documentation generation process using Gradle or the Grails CLI.

```bash
gradle docs
```

```bash
grails doc
```

--------------------------------

### Start Grails Application

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Executes the embedded server on port 8080.

```shell
grails> run-app
```

--------------------------------

### static void main(java.lang.String[] args)

Source: https://grails.apache.org/docs/3.3.18/api/grails/ui/script/GrailsApplicationScriptRunner.html

The main entry point to run an existing Application class. The last argument is the Application class name, and all other arguments are script names.

```APIDOC
## static void main(java.lang.String[] args)

### Description
Main method to run an existing Application class.

### Parameters
- **args** (java.lang.String[]) - Required - The last argument is the Application class name. All other args are script names.
```

--------------------------------

### withFormat without wildcard

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

Example of withFormat behavior when no wildcard block is provided.

```groovy
withFormat {
    html bookList: books
    json { render books as JSON }
    xml { render books as XML }
}
```

--------------------------------

### publishGuide()

Source: https://grails.apache.org/docs/3.3.18/api/grails/doc/gradle/PublishGuide.html

The publishGuide method is the primary task action for generating and publishing documentation.

```APIDOC
## publishGuide()

### Description
Executes the documentation publishing process for the project.

### Method
TaskAction

### Parameters
- **asciidoc** (boolean) - Optional - Configuration for AsciiDoc processing.
- **language** (String) - Optional - Specifies the language for the documentation.
- **macros** (Collection) - Required - Collection of macros to be used.
- **properties** (Properties) - Optional - Configuration properties.
- **propertiesFiles** (List) - Optional - List of property files.
- **resourcesDir** (File) - Optional - Directory containing resources.
- **sourceDir** (File) - Required - Directory containing source files.
- **sourceRepo** (String) - Optional - Source repository URL.
- **targetDir** (File) - Required - Output directory for published documentation.
- **workDir** (File) - Required - Working directory for the task.
```

--------------------------------

### Example JSON Output

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

Sample JSON representation produced by the respond method.

```JSON
[
    {id:1,"title":"The Stand"},
    {id:2,"title":"Shining"}
]
```

--------------------------------

### Define Domain Class

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/findOrSaveBy.html

Example domain class used for demonstrating findOrSaveBy.

```groovy
class Book {
   String title
   String author
}
```

--------------------------------

### Retrieve domain instances using getAll

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/getAll.html

Demonstrates retrieving domain instances using variable arguments, a list of IDs, or fetching all instances.

```groovy
// get a list which contains Book instances with ids 2, 1, 3 respectively
def bookList = Book.getAll(2, 1, 3)

// can take a list of ids as only argument, very
// useful when the ids list is calculated in code
def bookList = Book.getAll([1, 2, 3])

// when called without arguments returns list of all objects
def bookList = Book.getAll()
```

--------------------------------

### Create Grails application and plugin

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Initialize a new application and plugin in a parent directory to prepare for a multi-project build.

```bash
$ grails create-app myapp
$ grails create-plugin myplugin
```

--------------------------------

### generate-views Command Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/generate-views.html

Common usage patterns for generating views for specific domain classes or all classes using a wildcard.

```bash
grails generate-views
grails generate-views org.bookstore.Book
grails generate-views "*"
```

--------------------------------

### Example of a specific resource path

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/io/support/PathMatchingResourcePatternResolver.html

A representation of a single XML resource path.

```text
     com/mycompany/package1/service-context.xml
```

--------------------------------

### get(int index)

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/web/json/JSONArray.html

Retrieves the object value associated with the specified index.

```APIDOC
## get(int index)

### Description
Get the object value associated with an index.

### Parameters
- **index** (int) - Required - The index must be between 0 and length() - 1.

### Returns
- **Object** - An object value.

### Throws
- **JSONException** - If there is no value for the index.
```

--------------------------------

### Navigate to Project Directory

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Change the current working directory to the newly created project folder.

```text
cd helloworld
```

--------------------------------

### nextTo(char d)

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/web/json/JSONTokener.html

Get the text up but not including the specified character or the end of line.

```APIDOC
## public java.lang.String nextTo(char d)

### Description
Get the text up but not including the specified character or the end of line, whichever comes first.

### Parameters
- **d** (char) - A delimiter character.

### Returns
- **String** - The extracted string.
```

--------------------------------

### getPathFromRoot(java.lang.String path)

Source: https://grails.apache.org/docs/3.3.18/api/org/grails/io/support/GrailsResourceUtils.html

Get the path relative to an artefact folder under grails-app.

```APIDOC
### public static java.lang.String getPathFromRoot(java.lang.String path)

#### Description
Get the path relative to an artefact folder under grails-app.

#### Parameters
- **path** (java.lang.String) - The path to evaluate

#### Returns
- (java.lang.String) - The path relative to the root folder grails-app
```

--------------------------------

### run(String... args)

Source: https://grails.apache.org/docs/3.3.18/api/grails/ui/script/GrailsApplicationScriptRunner.html

Executes the application with the provided arguments and returns the configured application context.

```APIDOC
## org.springframework.context.ConfigurableApplicationContext run(java.lang.String... args)

### Description
Runs the Grails application with the specified arguments.

### Parameters
- **args** (String...) - Required - Arguments for the application execution.

### Response
- **Return Type** (ConfigurableApplicationContext) - The configured application context.
```

--------------------------------

### Run Grails Application

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Starts the application using the built-in Tomcat server.

```bash
grails run-app
```

```bash
grails run-app -port=8090
```

--------------------------------

### Limit Bound Properties

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Example of retrieving a domain instance for secure property updates.

```groovy
def p = Person.get(1)
```

--------------------------------

### Implement the Show Action

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Implementation of the show action using automatic domain instance lookup.

```groovy
def show(Book book) {
    respond book
}
```

```groovy
def show(Book book) {
    if(book == null) {
        render status:404
    }
    else {
        return [book: book]
    }
}
```

--------------------------------

### Configure Plugin Dependency

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Example of declaring a plugin dependency in a Grails project configuration.

```groovy
- "org.grails.plugins:myplugin2:1.0"
```

--------------------------------

### Create a Grails Application

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Commands to initialize a new Grails application using the default or a specific profile.

```bash
grails create-app myapp
```

```bash
grails create-app myapp --profile=rest-api
```

--------------------------------

### Accept header examples

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

Common Accept header values sent by browsers and clients.

```text
*/*
```

```text
text/xml, application/xml, application/xhtml+xml, text/html;q=0.9, \
    text/plain;q=0.8, image/png, */*;q=0.5
```

```text
application/json
```

--------------------------------

### Define post-creation instructions in profile.yml

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Specify text to display to the user after application creation.

```yaml
instructions: Here are some instructions
```

--------------------------------

### Criteria Projections Example

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/createCriteria.html

Using projections to count distinct values in a criteria query.

```Groovy
def c = Account.createCriteria()
def branchCount = c.get {
    projections {
        countDistinct "branch"
    }
}
```

--------------------------------

### Generate Application Skeleton

Source: https://grails.apache.org/docs/3.3.18/guide/gettingStarted.html

Use the generate-all command to create a controller, unit test, and views for a domain class.

```bash
grails generate-all helloworld.Book
```

--------------------------------

### Custom Renderer Output Format

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Example of the XML output generated by the custom BookXmlRenderer.

```xml
<book id="1" title="The Stand"/>
```

--------------------------------

### Command Usage Syntax

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/plugin-info.html

The standard syntax for executing the plugin-info command.

```bash
grails plugin-info <<name>>
```

--------------------------------

### REST Response Formats

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Example XML and JSON responses returned by the RESTful resource.

```xml
<?xml version="1.0" encoding="UTF-8"?>
<book id="1">
    <title>The Stand</title>
</book>
```

```json
{"id":1,"title":"The Stand"}
```

--------------------------------

### Command Usage Syntax

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-app.html

General syntax for executing the create-app command with optional profile and feature flags.

```bash
grails create-app <<name>> [--profile] <<profile name>> [--features] <<FEATURE NAMES>>
```

--------------------------------

### Environment-specific war commands

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/war.html

Examples of running the war command in different Grails environments.

```bash
grails test war
grails dev war
grails prod war
```

--------------------------------

### Create Application In-Place

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-app.html

Initializes a new Grails application within the current working directory.

```bash
$ mkdir bookstore
$ cd bookstore
$ grails create-app --inplace
```

--------------------------------

### Advanced DataSource Configuration

Source: https://grails.apache.org/docs/3.3.18/guide/conf.html

Example of configuring advanced connection pool properties for the DataSource.

```groovy
dataSource {
    pooled = true
    dbCreate = "update"
    url = "jdbc:mysql://localhost:3306/my_database"
    driverClassName = "com.mysql.jdbc.Driver"
    dialect = org.hibernate.dialect.MySQL5InnoDBDialect
    username = "username"
    password = "password"
    type = "com.zaxxer.hikari.HikariDataSource"
    properties {
       // Documentation for Tomcat JDBC Pool
       // http://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html#Common_Attributes
       // https://tomcat.apache.org/tomcat-7.0-doc/api/org/apache/tomcat/jdbc/pool/PoolConfiguration.html
       jmxEnabled = true
       initialSize = 5
       maxActive = 50
       minIdle = 5
       maxIdle = 25
       maxWait = 10000
       maxAge = 10 * 60000
       timeBetweenEvictionRunsMillis = 5000
       minEvictableIdleTimeMillis = 60000
       validationQuery = "SELECT 1"
       validationQueryTimeout = 3
       validationInterval = 15000
```

--------------------------------

### Run Full Test Suite

Source: https://grails.apache.org/docs/3.3.18/guide/contributing.html

Execute the complete set of tests for the project.

```bash
./gradlew test
```

--------------------------------

### Per-Environment Bootstrapping

Source: https://grails.apache.org/docs/3.3.18/guide/conf.html

Execute environment-specific logic during application startup within BootStrap.groovy.

```groovy
def init = { ServletContext ctx ->
    environments {
        production {
            ctx.setAttribute("env", "prod")
        }
        development {
            ctx.setAttribute("env", "dev")
        }
    }
    ctx.setAttribute("foo", "bar")
}
```

--------------------------------

### Define i18n Message

Source: https://grails.apache.org/docs/3.3.18/guide/validation.html

Example of a message entry in messages.properties for a specific constraint violation.

```properties
user.login.blank=Your login name must be specified!
```

--------------------------------

### Generate documentation locally

Source: https://grails.apache.org/docs/3.3.18/guide/contributing.html

Gradle command to build the documentation, excluding the API documentation task for faster execution.

```bash
$ ./gradlew publishGuide -x apiDocs
```

--------------------------------

### Execute HQL Queries with executeQuery

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/executeQuery.html

Examples demonstrating various ways to invoke executeQuery, including parameter passing, pagination, and Hibernate-specific configuration options.

```Groovy
// simple query
Account.executeQuery("select distinct a.number from Account a")

// using with list of parameters
Account.executeQuery("select distinct a.number from Account a " +
                     "where a.branch = ? and a.created > ?",
                     ['London', lastMonth])

// using with a single parameter and pagination params
Account.executeQuery("select distinct a.number from Account a " +
                     "where a.branch = ?", ['London'],
                     [max: 10, offset: 5])

// using with Map of named parameters
Account.executeQuery("select distinct a.number from Account a " +
                     "where a.branch = :branch",
                     [branch: 'London'])

// using with Map of named parameters and pagination params
Account.executeQuery("select distinct a.number from Account a " +
                     "where a.branch = :branch",
                     [branch: 'London', max: 10, offset: 5])

// same as previous
Account.executeQuery("select distinct a.number from Account a " +
                     "where a.branch = :branch",
                     [branch: 'London'], [max: 10, offset: 5])

// tell underlying Hibernate Query object to not attach newly retrieved
// objects to the session, will only save with explicit `save`
Account.executeQuery("select distinct a.number from Account a",
                     null, [readOnly: true])

// time request out after 18 seconds
Account.executeQuery("select distinct a.number from Account a",
                     null, [timeout: 18])

// have Hibernate Query object return 30 rows at a time
Account.executeQuery("select distinct a.number from Account a",
                     null, [fetchSize: 30])

// modify the FlushMode of the Query (default is `FlushMode.AUTO`)
Account.executeQuery("select distinct a.number from Account a",
                     null, [flushMode: FlushMode.MANUAL])
```

--------------------------------

### Execute a command with arguments

Source: https://grails.apache.org/docs/3.3.18/guide/commandLine.html

Example of invoking a command that utilizes defined flags and arguments.

```bash
grails generate-all MyClass --force
```

--------------------------------

### Read Domain Instance

Source: https://grails.apache.org/docs/3.3.18/guide/GORM.html

Retrieving instances using get, read, and load methods.

```groovy
def p = Person.get(1)
assert 1 == p.id
```

```groovy
def p = Person.read(1)
```

```groovy
def p = Person.load(1)
```

--------------------------------

### Responding with a Map and Arguments

Source: https://grails.apache.org/docs/3.3.18/ref/Controllers/respond.html

Illustrates the correct syntax for responding with a Map and arguments to avoid parameter reversal.

```Groovy
respond([:], status: 200)
```

--------------------------------

### REST Resource JSON Response

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Example JSON output format for a REST resource request.

```json
{"id":1,"title":"The Stand"}
```

--------------------------------

### REST Resource XML Response

Source: https://grails.apache.org/docs/3.3.18/guide/single.html

Example XML output format for a REST resource request.

```xml
<?xml version="1.0" encoding="UTF-8"?>
<book id="1">
    <title>The Stand</title>
</book>
```

--------------------------------

### Render a Domain Instance in a Template

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Basic template syntax for rendering a Book domain instance.

```groovy
model {
    Book book
}

json g.render(book)
```

--------------------------------

### Create a Grails plugin

Source: https://grails.apache.org/docs/3.3.18/ref/Command%20Line/create-plugin.html

Initializes a new Grails plugin project with the specified name.

```bash
grails create-plugin simple
```

```bash
grails create-plugin <<name>>
```

--------------------------------

### main(String[] args)

Source: https://grails.apache.org/docs/3.3.18/api/grails/ui/console/GrailsSwingConsole.html

The main method used to run an existing Application class.

```APIDOC
## static void main(String[] args)

### Description
Main method to run an existing Application class.

### Parameters
- **args** (String[]) - Required - Command line arguments.
```

--------------------------------

### Criteria Method Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Domain%20Classes/createCriteria.html

Common criteria methods for filtering and ordering domain class queries.

```Groovy
between("balance", 500, 1000)
```

```Groovy
eq("branch", "London")
```

```Groovy
eq("branch", "london", [ignoreCase: true])
```

```Groovy
eqProperty("lastTx", "firstTx")
```

```Groovy
gt("balance",1000)
```

```Groovy
gtProperty("balance", "overdraft")
```

```Groovy
ge("balance", 1000)
```

```Groovy
geProperty("balance", "overdraft")
```

```Groovy
idEq(1)
```

```Groovy
ilike("holderFirstName", "Steph%")
```

```Groovy
'in'("age",[18..65]) or not {'in'("age",[18..65])}
```

```Groovy
isEmpty("transactions")
```

```Groovy
isNotEmpty("transactions")
```

```Groovy
isNull("holderGender")
```

```Groovy
isNotNull("holderGender")
```

```Groovy
lt("balance", 1000)
```

```Groovy
ltProperty("balance", "overdraft")
```

```Groovy
le("balance", 1000)
```

```Groovy
leProperty("balance", "overdraft")
```

```Groovy
like("holderFirstName", "Steph%")
```

```Groovy
ne("branch", "London")
```

```Groovy
neProperty("lastTx", "firstTx")
```

```Groovy
order("holderLastName", "desc")
```

```Groovy
rlike("holderFirstName", /Steph.+/)
```

```Groovy
sizeEq("transactions", 10)
```

```Groovy
sizeGt("transactions", 10)
```

```Groovy
sizeGe("transactions", 10)
```

```Groovy
sizeLt("transactions", 10)
```

```Groovy
sizeLe("transactions", 10)
```

```Groovy
sizeNe("transactions", 10)
```

```Groovy
sqlRestriction "char_length(first_name) = 4"
```

--------------------------------

### Data Binding Examples

Source: https://grails.apache.org/docs/3.3.18/ref/Controllers/bindData.html

Demonstrates various ways to bind request parameters to a target object, including filtering by property names and prefixes.

```groovy
// binds request parameters to a target object
bindData(target, params)

// exclude firstName and lastName
bindData(target, params, [exclude: ['firstName', 'lastName']])

// only use parameters starting with "author." e.g. author.email
bindData(target, params, "author")
bindData(target, params, [exclude: ['firstName', 'lastName']], "author")

// using inclusive map
bindData(target, params, [include: ['firstName', 'lastName']], "author")
```

--------------------------------

### Custom Link Output Example

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

The resulting JSON output after applying a custom link to a resource.

```json
{
  "_links": {
    "self": {
      "href": "http://localhost:8080/books/1",
      "hreflang": "en",
      "type": "application/vnd.books.org.book+json"
    }
    "publisher": {
        "href": "http://localhost:8080/books/1/publisher",
        "hreflang": "en"
    }
  },
  "title": "\"The Stand\""
}
```

--------------------------------

### Create Application with Custom Profile

Source: https://grails.apache.org/docs/3.3.18/guide/profiles.html

Commands to create an application using a specific profile artifact or a configured default.

```bash
$ grails create-app myapp --profile=com.mycompany.grails.profiles:myprofile:1.0.0
```

```bash
$ grails create-app myapp --profile=myprofile
```

--------------------------------

### JSON View Output

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

The resulting JSON output produced by the basic JSON view example.

```JSON
{"person":{"name":"bob"}}
```

--------------------------------

### Initialize Object with Map

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

Demonstrates creating a new object instance using a map of values.

```groovy
def bindingMap = [firstName: 'Peter', lastName: 'Gabriel', age: 63]

def person = new Person(bindingMap)

assert person.firstName == 'Peter'
assert person.lastName == 'Gabriel'
assert person.age == 63
```

--------------------------------

### Execute Application Tasks

Source: https://grails.apache.org/docs/3.3.18/guide/REST.html

Commands to run the server, client, or both applications using Gradle.

```bash
./gradlew server:bootRun
```

```bash
./gradlew client:bootRun
```

```bash
./gradlew bootRun --parallel
```

--------------------------------

### Model Merging Example

Source: https://grails.apache.org/docs/3.3.18/ref/Controllers/chain.html

Demonstrates how the chained model is merged with the model returned by the target action.

```groovy
def one() {
    chain action: 'two', model: [name: 'Tony', town: 'Birmingham']
}

def two() {
    [name: 'Anthony', country: 'England']
}
```

--------------------------------

### Basic max constraint usage

Source: https://grails.apache.org/docs/3.3.18/ref/Constraints/max.html

Examples of applying the max constraint to different property types.

```groovy
age max: new Date()
price max: 999F
```

--------------------------------

### Populate Map via Binding Map

Source: https://grails.apache.org/docs/3.3.18/guide/theWebLayer.html

Example of initializing a domain object with a map containing key-based player data.

```groovy
def bindingMap = [title: 'The Lamb Lies Down On Broadway',
                  'players[guitar]': [name: 'Steve Hackett'],
                  'players[vocals]': [name: 'Peter Gabriel'],
                  'players[keyboards]': [name: 'Tony Banks']]

def album = new Album(bindingMap)

assert album.title == 'The Lamb Lies Down On Broadway'
assert album.players.size() == 3
assert album.players.guitar.name == 'Steve Hackett'
assert album.players.vocals.name == 'Peter Gabriel'
assert album.players.keyboards.name == 'Tony Banks'
```

--------------------------------

### Basic min constraint usage

Source: https://grails.apache.org/docs/3.3.18/ref/Constraints/min.html

Examples of applying the min constraint to different data types.

```groovy
age min: new Date()
price min: 0F
```
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