Java SE 24 & JDK 24

https://docs.oracle.com/en/java/javase/24/docs/api/
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### List Configurations or Start Recording with Configuration

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Configuration.html

This example demonstrates how to list available JFR configurations or start a recording with a specified configuration. It requires no special setup beyond standard Java imports.

```java
public static void main(String... args) throws Exception {
    if (args.length == 0) {
        System.out.println("Configurations:");
        for (Configuration c : Configuration.getConfigurations()) {
            System.out.println("Name: " + c.getName());
            System.out.println("Label: " + c.getLabel());
            System.out.println("Description: " + c.getDescription());
            System.out.println("Provider: " + c.getProvider());
            System.out.println();
        }
    } else {
        String name = args[0];
        Configuration c = Configuration.getConfiguration(name);
        try (Recording r = new Recording(c)) {
            System.out.println("Starting recording with settings:");
            for (Map.Entry<String, String> setting : c.getSettings().entrySet()) {
                System.out.println(setting.getKey() + " = " + setting.getValue());
            }
            r.start();
        }
    }
}
```

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

### Starting a Simple Process

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/ProcessBuilder.html

An example of how to start a new process using the default working directory and environment.

```APIDOC
## POST /api/startSimpleProcess

### Description
Starts a new operating system process with the specified command and arguments, using the default working directory and environment.

### Method
POST

### Endpoint
/api/startSimpleProcess

### Parameters
#### Request Body
- **command** (List<String>) - Required - The command and its arguments to execute.

### Request Example
```json
{
  "command": ["myCommand", "myArg"]
}
```

### Response
#### Success Response (200)
- **processId** (String) - The identifier of the started process.

#### Response Example
```json
{
  "processId": "12345"
}
```
```

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

### Configure, Start, Stop, and Dump Recording

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

This example demonstrates how to configure, start, stop, and dump recording data to a file using the `Recording` class. Ensure necessary imports for `Configuration`, `Recording`, `Files`, and `Thread`.

```java
Configuration c = Configuration.getConfiguration("default");
try (Recording r = new Recording(c)) {
    r.start();
    System.gc();
    Thread.sleep(5000);
    r.stop();
    r.dump(Files.createTempFile("my-recording", ".jfr"));
}
```

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

### Creating and Starting Threads

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/Thread.html

Examples of creating and starting platform and virtual threads using the `Thread.Builder` API.

```APIDOC
## Creating and Starting Threads

`Thread` defines public constructors for creating platform threads and the `start` method to schedule threads to execute. `Thread` may be extended for customization and other advanced reasons although most applications should have little need to do this.

`Thread` defines a `Thread.Builder` API for creating and starting both platform and virtual threads. The following are examples that use the builder:

```java
  Runnable runnable = ...

  // Start a daemon thread to run a task
  Thread thread = Thread.ofPlatform().daemon().start(runnable);

  // Create an unstarted thread with name "duke", its start() method
  // must be invoked to schedule it to execute.
  Thread thread = Thread.ofPlatform().name("duke").unstarted(runnable);

  // A ThreadFactory that creates daemon threads named "worker-0", "worker-1", ...
  ThreadFactory factory = Thread.ofPlatform().daemon().name("worker-", 0).factory();

  // Start a virtual thread to run a task
  Thread thread = Thread.ofVirtual().start(runnable);

  // A ThreadFactory that creates virtual threads
  ThreadFactory factory = Thread.ofVirtual().factory();

```
```

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

### Example Usage

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

Demonstrates how to configure, start, stop, and dump recording data to disk using the Recording class.

```APIDOC
## Example: Recording Configuration and Management

### Description

This example shows the typical workflow for using the `Recording` class to capture and save profiling data.

### Code

```java
Configuration c = Configuration.getConfiguration("default");
try (Recording r = new Recording(c)) {
    r.start();
    System.gc();
    Thread.sleep(5000);
    r.stop();
    r.dump(Files.createTempFile("my-recording", ".jfr"));
}
```
```

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

### Configure and Start Recording with Event Settings

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/EventSettings.html

This example demonstrates how to use the EventSettings class to configure CPU load and file write events for a recording. It enables specific events, sets their properties like period and threshold, and then starts, stops, and dumps the recording.

```java
try (Recording r = new Recording()) {
    r.enable("jdk.CPULoad")
     .withPeriod(Duration.ofSeconds(1));
    r.enable("jdk.FileWrite")
     .withoutStackTrace()
     .withThreshold(Duration.ofNanos(10));
    r.start();
    Thread.sleep(10_000);
    r.stop();
    r.dump(Files.createTempFile("recording", ".jfr"));
}
```

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

### Starting a Process with Custom Attributes

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/ProcessBuilder.html

An example demonstrating how to configure a ProcessBuilder with a custom working directory, environment variables, and redirected output/error streams.

```APIDOC
## POST /api/startCustomProcess

### Description
Starts a new operating system process with custom attributes, including a modified working directory, environment variables, and redirection of standard output and error.

### Method
POST

### Endpoint
/api/startCustomProcess

### Parameters
#### Request Body
- **command** (List<String>) - Required - The command and its arguments to execute.
- **environment** (Map<String, String>) - Optional - A map of environment variables to set for the process.
- **workingDirectory** (String) - Optional - The path to the working directory for the process.
- **redirectErrorStream** (Boolean) - Optional - If true, merges standard error with standard output.
- **redirectOutputToFile** (String) - Optional - The path to a file to which standard output should be redirected. Supports appending.

### Request Example
```json
{
  "command": ["myCommand", "myArg1", "myArg2"],
  "environment": {
    "VAR1": "myValue",
    "VAR2": "myValueSuffix"
  },
  "workingDirectory": "/path/to/myDir",
  "redirectErrorStream": true,
  "redirectOutputToFile": "/path/to/log.txt"
}
```

### Response
#### Success Response (200)
- **processId** (String) - The identifier of the started process.

#### Response Example
```json
{
  "processId": "67890"
}
```
```

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

### Create Recording with Configuration Object

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

This constructor creates a recording using a predefined Configuration object. The example demonstrates creating a recording with the default configuration. The recording is initially in the NEW state and needs to be started manually.

```java
Recording r = new Recording(Configuration.getConfiguration("default"));
```

```java
public Recording(Configuration configuration)
```

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

### Create Recording with Map Settings

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

Use this constructor to create a recording initialized with settings provided in a map. The recording starts in the NEW state and must be explicitly started using the start() method. Ensure the settings map is not null.

```java
public Recording(Map<String,String> settings)
```

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

### Start a Process with Default Settings

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/ProcessBuilder.html

This snippet demonstrates how to start a new process using the default working directory and environment settings.

```java
Process p = new ProcessBuilder("myCommand", "myArg").start();
```

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

### Create a DynamicLinker Instance

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.dynalink/jdk/dynalink/DynamicLinker.html

Example of setting up a DynamicLinker with a prioritized linker and creating it using DynamicLinkerFactory. This setup is often a starting point for integrating custom language runtimes.

```java
class MyLanguageRuntime {
    private static final GuardingDynamicLinker myLanguageLinker = new MyLanguageLinker();
    private static final DynamicLinker dynamicLinker = createDynamicLinker();

    private static DynamicLinker createDynamicLinker() {
        final DynamicLinkerFactory factory = new DynamicLinkerFactory();
        factory.setPrioritizedLinker(myLanguageLinker);
        return factory.createLinker();
    }

    public static CallSite bootstrap(MethodHandles.Lookup lookup, String name, MethodType type) {
        return dynamicLinker.link(
            new SimpleRelinkableCallSite(
                new CallSiteDescriptor(lookup, parseOperation(name), type)));
    }

    private static Operation parseOperation(String name) {
        ...
    }
 }
```

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

### Instantiating and Loading a KeyStore

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/security/KeyStore.html

Demonstrates various ways to get a KeyStore instance and load its contents, including specifying a file, using the default type, or providing a specific type.

```APIDOC
## Instantiating and Loading a KeyStore

### Description
This section covers how to obtain a `KeyStore` instance and load its entries, which is a prerequisite for accessing or modifying its contents.

### Getting a KeyStore Instance

1.  **Specify an existing keystore file:**
    ```java
    // get keystore password
    char[] password = getPassword();

    // probe the keystore file and load the keystore entries
    KeyStore ks = KeyStore.getInstance(new File("keyStoreName"), password);
    ```
    *   The system automatically determines the keystore type from the file.
    *   Entries are loaded upon instantiation; no separate `load` call is needed.

2.  **Rely on the default type:**
    ```java
    KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
    ```
    *   Returns a keystore implementation of the system's default type.

3.  **Provide a specific keystore type:**
    ```java
    KeyStore ks = KeyStore.getInstance("JKS");
    ```
    *   Returns the preferred implementation for the specified type (e.g., "JKS").

### Loading KeyStore Entries

*   Before accessing entries, the keystore must be loaded, unless it was loaded during instantiation.

    ```java
    KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());

    // get user password and file input stream
    char[] password = getPassword();

    try (FileInputStream fis = new FileInputStream("keyStoreName")) {
        ks.load(fis, password);
    }
    ```

*   To create an empty keystore, pass `null` as the `InputStream` argument to the `load` method.

### Accessing and Storing Entries

*   After loading, entries can be read or written.

    ```java
    KeyStore.PasswordProtection protParam = new KeyStore.PasswordProtection(password);
    try (FileOutputStream fos = new FileOutputStream("newKeyStoreName")) {
        // get my private key
        KeyStore.PrivateKeyEntry pkEntry = (KeyStore.PrivateKeyEntry) ks.getEntry("privateKeyAlias", protParam);
        PrivateKey myPrivateKey = pkEntry.getPrivateKey();

        // save my secret key
        javax.crypto.SecretKey mySecretKey;
        KeyStore.SecretKeyEntry skEntry = new KeyStore.SecretKeyEntry(mySecretKey);
        ks.setEntry("secretKeyAlias", skEntry, protParam);

        // store away the keystore
        ks.store(fos, password);
    } finally {
        protParam.destroy();
    }
    ```
```

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

### Get Recording Start Time

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

Returns the Instant when the recording was started. If the recording has not been started, this method returns null.

```java
public Instant getStartTime()
```

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

### GET - Absolute Bulk Get

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/nio/ByteBuffer.html

Transfers bytes from the buffer to a destination array starting at a specified index.

```APIDOC
## GET /api/buffer/get

### Description
Absolute bulk get method. Transfers `length` bytes from this buffer into the given array, starting at the given index in this buffer and at the given offset in the array. The position of this buffer is unchanged.

### Method
GET

### Endpoint
`/api/buffer/get`

### Parameters
#### Path Parameters
- **index** (int) - Required - The index in this buffer from which the first byte will be read; must be non-negative and less than `limit()`
- **dst** (byte[]) - Required - The destination array
- **offset** (int) - Required - The offset within the array of the first byte to be written; must be non-negative and less than `dst.length`
- **length** (int) - Required - The number of bytes to be written to the given array; must be non-negative and no larger than the smaller of `limit() - index` and `dst.length - offset`

### Response
#### Success Response (200)
- **This buffer** (ByteBuffer) - Returns the current buffer instance.

#### Response Example
```json
{
  "example": "ByteBuffer instance"
}
```

### Throws
- **IndexOutOfBoundsException** - If the preconditions on the `index`, `offset`, and `length` parameters do not hold
```

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

### Example of getting ActionListeners

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/java/awt/MenuItem.html

This example demonstrates how to query a MenuItem for its action listeners using the getListeners method.

```java
ActionListener[] als = (ActionListener[])(m.getListeners(ActionListener.class));
```

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

### Configuration Syntax Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/javax/security/auth/login/Configuration.html

Illustrates the default syntax for a Configuration entry, showing how applications, LoginModules, flags, and options are defined.

```APIDOC
### Configuration Syntax Example

```
      Name {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
      Name {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
      other {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
```

**Explanation:**
- **Name**: Application name index.
- **ModuleClass**: Fully qualified class name of the LoginModule.
- **Flag**: Controls the behavior of the LoginModule (Required, Requisite, Sufficient, Optional).
- **ModuleOptions**: Space-separated list of LoginModule-specific values (e.g., `debug="true"`).
```

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

### Configure and Start a Process

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/ProcessBuilder.html

This example shows how to configure a ProcessBuilder with a modified working directory, environment variables, and redirects standard output and error to a log file. It also demonstrates redirecting error output to merge with standard output.

```java
ProcessBuilder pb = new ProcessBuilder("myCommand", "myArg1", "myArg2");
Map<String, String> env = pb.environment();
env.put("VAR1", "myValue");
env.remove("OTHERVAR");
env.put("VAR2", env.get("VAR1") + "suffix");
pb.directory(new File("myDir"));
File log = new File("log");
pb.redirectErrorStream(true);
pb.redirectOutput(Redirect.appendTo(log));
Process p = pb.start();
assert pb.redirectInput() == Redirect.PIPE;
assert pb.redirectOutput().file() == log;
```

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

### SimpleDateFormat Methods

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/text/SimpleDateFormat.html

Details on key methods for setting year start, getting year start, and formatting dates.

```APIDOC
## Method Details 

### set2DigitYearStart 
public void set2DigitYearStart(Date startDate)
Sets the 100-year period 2-digit years will be interpreted as being in to begin on the date the user specifies. 

Parameters:
    `startDate` - During parsing, two digit years will be placed in the range `startDate` to `startDate + 100 years`. 

Throws:
    `NullPointerException` - if `startDate` is `null`. 

Since:
    1.2 

See Also:
    
      * `get2DigitYearStart()`

### get2DigitYearStart 
public Date get2DigitYearStart()
Returns the beginning date of the 100-year period 2-digit years are interpreted as being within. 

Returns:
    the start of the 100-year period into which two digit years are parsed 

Since:
    1.2 

See Also:
    
      * `set2DigitYearStart(java.util.Date)`

### format 
public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition pos)
Formats the given `Date` into a date/time string and appends the result to the given `StringBuffer`. 

Specified by:
    `format` in class `DateFormat` 

Parameters:
    `date` - the date-time value to be formatted into a date-time string.     `toAppendTo` - where the new date-time text is to be appended.     `pos` - keeps track on the position of the field within the returned string. For example, given a date-time text `"1996.07.10 AD at 15:08:56 PDT"`, if the given `fieldPosition` is `DateFormat.YEAR_FIELD`, the begin index and end index of `fieldPosition` will be set to 0 and 4, respectively. Notice that if the same date-time field appears more than once in a pattern, the `fieldPosition` will be set for the first occurrence of that date-time field. For instance, formatting a `Date` to the date-time string `"1 PM PDT (Pacific Daylight Time)"` using the pattern `"h a z (zzzz)"` and the alignment field `DateFormat.TIMEZONE_FIELD`, the begin index and end index of `fieldPosition` will be set to 5 and 8, respectively, for the first occurrence of the timezone pattern character `'z'`.

Returns:
    the formatted date-time string. 

Throws:
    `NullPointerException` - if any of the parameters is `null`.

### formatToCharacterIterator 
public AttributedCharacterIterator formatToCharacterIterator(Object obj)
Formats an Object producing an `AttributedCharacterIterator`. You can use the returned `AttributedCharacterIterator` to build the resulting String, as well as to determine information about the resulting String. 
Each attribute key of the AttributedCharacterIterator will be of type `DateFormat.Field`, with the corresponding attribute value being the same as the attribute key. 

Overrides:
    `formatToCharacterIterator` in class `Format` 

Parameters:
    `obj` - The object to format 

Returns:
```

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

### Example: Creating SSLEngine with SNI

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/javax/net/ssl/SSLParameters.html

Example demonstrating how to create an SSLEngine with a specified server name, useful for SNI. Available since 1.8.

```java
     SSLEngine engine = 
         sslContext.createSSLEngine("www.example.com", 443);
 
```

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

### Get Document Start Position

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/javax/swing/text/Document.html

Returns a position that represents the start of the document. This position tracks changes and stays at the beginning.

```java
Position getStartPosition()
```

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

### Properties File Key-Value Examples

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/util/Properties.html

Demonstrates different ways to define key-value pairs in a properties file, including whitespace handling and the use of ':' or '=' as separators.

```properties
 Truth = Beauty
  Truth:Beauty
 Truth                    :Beauty
```

```properties
cheeses
```

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

### Get Start Point of Gradient

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/java/awt/LinearGradientPaint.html

Returns a copy of the start point of the gradient axis. This is a concrete method inherited from MultipleGradientPaint.

```java
Point2D getStartPoint()
```

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

### Get Text Start Offset - XMLStreamReader

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.xml/javax/xml/stream/util/StreamReaderDelegate.html

Returns the starting offset within the text character array for the current text event.

```java
public int getTextStart()
```

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

### Example Usage of HttpsConfigurator

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.httpserver/com/sun/net/httpserver/HttpsConfigurator.html

An example demonstrating how to configure HTTPS parameters using HttpsConfigurator.

```APIDOC
## Example Usage

```java
SSLContext sslContext = SSLContext.getInstance (....);
HttpsServer server = HttpsServer.create();

server.setHttpsConfigurator (new HttpsConfigurator(sslContext) {
    public void configure (HttpsParameters params) {

        // get the remote address if needed
        InetSocketAddress remote = params.getClientAddress();

        SSLContext c = getSSLContext();

        // get the default parameters
        SSLParameters sslparams = c.getDefaultSSLParameters();
        if (remote.equals (...) ) {
            // modify the default set for client x
        }

        params.setSSLParameters(sslparams);
    }
});
```
```

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

### JarSigner Example Usage

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jartool/jdk/security/jarsigner/JarSigner.html

An example demonstrating how to create and use a JarSigner object.

```APIDOC
### Example
```java
    JarSigner signer = new JarSigner.Builder(key, certPath)
            .digestAlgorithm("SHA-256")
            .signatureAlgorithm("SHA256withRSA")
            .build();
    try (ZipFile  in = new ZipFile(inputFile);
            FileOutputStream out = new FileOutputStream(outputFile)) {
        signer.sign(in, out);
    }
```
```

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

### Create Simple File Server

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.httpserver/com/sun/net/httpserver/SimpleFileServer.html

Demonstrates how to create and start a simple HTTP file server using the createFileServer static factory method.

```APIDOC
## Simple File Server

The `createFileServer` static factory method returns an `HttpServer` that is a simple out-of-the-box file server. The server comes with an initial handler that serves files from a given directory path (and its subdirectories). The output level determines what log messages are printed to `System.out`, if any.

### Method
`static HttpServer createFileServer(InetSocketAddress addr, Path rootDirectory, SimpleFileServer.OutputLevel outputLevel)`

### Endpoint
N/A (This is a Java API, not a direct HTTP endpoint)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```java
var addr = new InetSocketAddress(8080);
var server = SimpleFileServer.createFileServer(addr, Path.of("/some/path"), OutputLevel.INFO);
server.start();
```

### Response
#### Success Response (200)
N/A (This is a Java API, not a direct HTTP endpoint)

#### Response Example
N/A
```

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

### Get Scanline Stride

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/java/awt/image/SinglePixelPackedSampleModel.html

Returns the scanline stride of this SinglePixelPackedSampleModel. This is the number of data elements between the start of one scanline and the start of the next.

```java
public int getScanlineStride()

```

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

### Default Configuration Syntax Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/javax/security/auth/login/Configuration.html

Illustrates the default syntax for a Configuration object, showing application-specific entries with LoginModules, flags, and options.

```plaintext
      Name {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
      Name {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
      other {
            ModuleClass  Flag    ModuleOptions;
            ModuleClass  Flag    ModuleOptions;
      };
 
```

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

### Get Matcher Region Start Index

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/util/regex/Matcher.html

Reports the starting index (inclusive) of the region within the input sequence that the matcher searches.

```Java
int regionStart = matcher.regionStart();
```

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

### Get Generic Listeners by Type

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/javax/swing/tree/DefaultTreeModel.html

Retrieves all listeners of a specified type registered with the model. For example, to get all TreeModelListeners, use `TreeModelListener.class`.

```java
public <T extends EventListener> T[] getListeners(Class<T> listenerType)
```

```java
TreeModelListener[] tmls = (TreeModelListener[])(m.getListeners(TreeModelListener.class));
```

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

### Convenience Method Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/io/File.html

Demonstrates the usage of a convenience method for setting file permissions, which internally calls a more detailed version.

```java
file.setWritable(arg, true)

```

```java
file.setReadable(arg, true)

```

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

### Get Code Array Start Index

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/classfile/attribute/CharacterRangeInfo.html

Returns the start index within the code array, inclusive. This indicates the beginning of a code segment.

```java
int startPc()
```

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

### Start Recording

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

Call this method to start an active recording. It is recommended to configure recording options and event settings before invoking start() for better consistency and performance. After a successful call, the recording enters the RUNNING state. This method throws an IllegalStateException if the recording is already started or closed.

```java
public void start()
```

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

### RecordingStream Usage Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/consumer/RecordingStream.html

An example demonstrating how to use RecordingStream to record and print specific JVM events.

```APIDOC
## Example: Recording JVM Events

This example shows how to record events using the default configuration and print the Garbage Collection, CPU Load, and JVM Information events to standard output.

```java
Configuration c = Configuration.getConfiguration("default");
try (var rs = new RecordingStream(c)) {
    rs.onEvent("jdk.GarbageCollection", System.out::println);
    rs.onEvent("jdk.CPULoad", System.out::println);
    rs.onEvent("jdk.JVMInformation", System.out::println);
    rs.start();
}
```
```

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

### initialize Method Details

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.security.auth/com/sun/security/auth/module/JndiLoginModule.html

Detailed explanation of the `initialize` method, its parameters, and its role in setting up the LoginModule.

```APIDOC
## Method Details

### `initialize`
```java
public void initialize(Subject subject, CallbackHandler callbackHandler, Map<String,?> sharedState, Map<String,?> options)
```
Initialize this `LoginModule`.

Parameters:
- `subject` (Subject) - the `Subject` to be authenticated.
- `callbackHandler` (CallbackHandler) - a `CallbackHandler` for communicating with the end user (prompting for usernames and passwords, for example).
- `sharedState` (Map<String,?>) - shared `LoginModule` state.
- `options` (Map<String,?>) - options specified in the login `Configuration` for this particular `LoginModule`.
```

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

### Get Listeners of a Specific Type

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/javax/swing/DefaultBoundedRangeModel.html

Use this method to retrieve an array of listeners of a specified type. For example, to get all ChangeListeners, pass ChangeListener.class.

```java
ChangeListener[] cls = (ChangeListener[])(m.getListeners(ChangeListener.class));
```

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

### Dynamic Event Creation Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/EventFactory.html

Example demonstrating how to implement a dynamic Event class using EventFactory.

```APIDOC
## Example: Dynamic Event Creation

### Description
This example shows how to implement a dynamic `Event` class using `EventFactory`.

### Code
```java
List<ValueDescriptor> fields = new ArrayList<>();
List<AnnotationElement> messageAnnotations = Collections.singletonList(new AnnotationElement(Label.class, "Message"));
fields.add(new ValueDescriptor(String.class, "message", messageAnnotations));
List<AnnotationElement> numberAnnotations = Collections.singletonList(new AnnotationElement(Label.class, "Number"));
fields.add(new ValueDescriptor(int.class, "number", numberAnnotations));

String[] category = { "Example", "Getting Started" };
List<AnnotationElement> eventAnnotations = new ArrayList<>();
eventAnnotations.add(new AnnotationElement(Name.class, "com.example.HelloWorld"));
eventAnnotations.add(new AnnotationElement(Label.class, "Hello World"));
eventAnnotations.add(new AnnotationElement(Description.class, "Helps programmer getting started"));
eventAnnotations.add(new AnnotationElement(Category.class, category));

EventFactory f = EventFactory.create(eventAnnotations, fields);

Event event = f.newEvent();
event.set(0, "hello, world!");
event.set(1, 4711);
event.commit();
```
```

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

### Example Execution Control Specifications

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jshell/jdk/jshell/spi/package-summary.html

Illustrates various ways to specify an ExecutionControl provider, including local, remote JDI, and failover configurations. These examples show how to pass parameters to different execution engines.

```plaintext
local
jdi:hostname(localhost)
failover:1(jdi),2(jdi:launch(true),timeout(3000)),3(local)
```

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

### Configure Https Parameters Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.httpserver/com/sun/net/httpserver/HttpsConfigurator.html

This example demonstrates how to override the configure method of HttpsConfigurator to customize SSL parameters for incoming HTTPS connections. It shows how to obtain the SSLContext and set SSLParameters.

```java
SSLContext sslContext = SSLContext.getInstance (....);
HttpsServer server = HttpsServer.create();

server.setHttpsConfigurator (new HttpsConfigurator(sslContext) {
    public void configure (HttpsParameters params) {

        // get the remote address if needed
        InetSocketAddress remote = params.getClientAddress();

        SSLContext c = getSSLContext();

        // get the default parameters
        SSLParameters sslparams = c.getDefaultSSLParameters();
        if (remote.equals (...) ) {
            // modify the default set for client x
        }

        params.setSSLParameters(sslparams);
    }
});
```

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

### Get Local Variable Start Scope

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/classfile/class-use/Label.html

Returns the Label indicating the start of the scope for a LocalVariable pseudo-instruction. This defines the range where the local variable is valid.

```java
Label LocalVariable.startScope()
```

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

### Example Usage

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/javax/swing/plaf/synth/ColorType.html

An example demonstrating how to create a custom SynthStyle using ColorType.

```APIDOC
## Example

```java
 class MyStyle extends SynthStyle {
     private Color disabledColor = new ColorUIResource(Color.RED);
     private Color color = new ColorUIResource(Color.BLACK);
     protected Color getColorForState(SynthContext context, ColorType type){
         if (context.getComponentState() == SynthConstants.DISABLED) {
             return disabledColor;
         }
         return color;
     }
 }
```
```

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

### RemoteRecordingStream Usage Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.management.jfr/jdk/management/jfr/RemoteRecordingStream.html

Example demonstrating how to use RemoteRecordingStream to record GC pauses and CPU usage on a remote host.

```APIDOC
## Example Usage

```java
     String host = "com.example";
     int port = 4711;

     String url = "service:jmx:rmi:///jndi/rmi://" + host + ":" + port + "/jmxrmi";

     JMXServiceURL u = new JMXServiceURL(url);
     JMXConnector c = JMXConnectorFactory.connect(u);
     MBeanServerConnection conn = c.getMBeanServerConnection();

     try (var rs = new RemoteRecordingStream(conn)) {
         rs.enable("jdk.GCPhasePause").withoutThreshold();
         rs.enable("jdk.CPULoad").withPeriod(Duration.ofSeconds(1));
         rs.onEvent("jdk.CPULoad", System.out::println);
         rs.onEvent("jdk.GCPhasePause", System.out::println);
         rs.start();
     }
```
```

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

### Example of using onExit with thenApply

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/Process.html

Demonstrates launching a process and using `onExit().thenApply()` to check if two files are identical based on the exit value.

```java
Process p = new ProcessBuilder("cmp", "f1", "f2").start();
Future<Boolean> identical = p.onExit().thenApply(p1 -> p1.exitValue() == 0);
...
if (identical.get()) { ... }
```

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

### Get Character Range Start Scope

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/classfile/class-use/Label.html

Returns the Label marking the start of the instruction range for a CharacterRange pseudo-instruction. This defines the scope of the character range.

```java
Label CharacterRange.startScope()
```

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

### Method: get

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/net/spi/InetAddressResolverProvider.html

Describes the abstract `get` method, which initializes and returns an `InetAddressResolver` provided by this provider. This method is called by `InetAddress` during system-wide resolver installation.

```APIDOC
## Method Details

### `public abstract InetAddressResolver get(InetAddressResolverProvider.Configuration configuration)`

Initialize and return an `InetAddressResolver` provided by this provider. This method is called by `InetAddress` when installing the system-wide resolver implementation.

Any error or exception thrown by this method is considered as a failure of `InetAddressResolver` instantiation and will be propagated to the caller of the method that triggered the lookup operation.

*Parameters:*
- `configuration` (InetAddressResolverProvider.Configuration) - a `InetAddressResolverProvider.Configuration` instance containing platform built-in address resolution configuration.

*Returns:*
the resolver provided by this provider
```

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

### X509Data Creation Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.xml.crypto/javax/xml/crypto/dsig/keyinfo/X509Data.html

Example of how to create an X509Data instance using KeyInfoFactory.

```APIDOC
## Creating X509Data

An `X509Data` instance may be created by invoking the `newX509Data` methods of the `KeyInfoFactory` class and passing it a list of one or more `XMLStructure`s representing X.509 content.

### Request Example
```java
KeyInfoFactory factory = KeyInfoFactory.getInstance("DOM");
X509Data x509Data = factory.newX509Data(Collections.singletonList("cn=Alice"));
```
```

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

### Usage Example 2: First Non-Null Result with Cancellation

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/util/concurrent/ExecutorCompletionService.html

An example demonstrating how to use ExecutorCompletionService to get the first non-null result and cancel other tasks.

```APIDOC
## Usage Example: First Non-Null Result with Cancellation

```java
void solve(Executor e,
            Collection<Callable<Result>> solvers)
    throws InterruptedException {
  CompletionService<Result> cs
      = new ExecutorCompletionService<>(e);
  int n = solvers.size();
  List<Future<Result>> futures = new ArrayList<>(n);
  Result result = null;
  try {
    solvers.forEach(solver -> futures.add(cs.submit(solver)));
    for (int i = n; i > 0; i--) {
      try {
        Result r = cs.take().get();
        if (r != null) {
          result = r;
          break;
        }
      } catch (ExecutionException ignore) {}
    }
  } finally {
    futures.forEach(future -> future.cancel(true));
  }

  if (result != null)
    use(result);
}
```
```

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

### X509Certificate Instantiation Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/javax/security/cert/X509Certificate.html

Provides sample code demonstrating how to instantiate an X509Certificate object from an InputStream or a byte array.

```APIDOC
## Instantiation Examples

### From InputStream
```java
InputStream inStream = new FileInputStream("fileName-of-cert");
X509Certificate cert = X509Certificate.getInstance(inStream);
inStream.close();
```

### From byte array
```java
byte[] certData = <certificate read from a file, say>;
X509Certificate cert = X509Certificate.getInstance(certData);
```

### Security Property Configuration

The instantiation process consults the `cert.provider.x509v1` security property to locate the actual implementation. A default implementation is used if this property is not set or accessible.

Example of setting the property:
```
cert.provider.x509v1=com.sun.security.cert.internal.x509.X509V1CertImpl
```
```

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

### Get Character Range Start Position

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/classfile/attribute/CharacterRangeInfo.html

Retrieves the encoded start of character positions in the source file, inclusive. This value is encoded as lineNumber << 10 + columnNumber.

```java
int characterRangeStart()
```

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

### Example Keystore Domain Configuration

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/security/DomainLoadStoreParameter.html

An example demonstrating a keystore domain named 'app1' with three keystores: 'app1-truststore', 'system-truststore', and 'app1-keystore', each with specified URIs and types.

```plaintext
 domain app1 {
     keystore app1-truststore
         keystoreURI="file:///app1/etc/truststore.jks";

     keystore system-truststore
         keystoreURI="${java.home}/lib/security/cacerts";

     keystore app1-keystore
         keystoreType="PKCS12"
         keystoreURI="file:///app1/etc/keystore.p12";
 };

 
```

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

### Schedule Recording Start

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/Recording.html

This method allows scheduling the start of a recording after a specified delay. After invocation, the recording enters the DELAYED state. The delay must not be null, and the recording must be in the NEW state prior to calling this method.

```java
public void scheduleStart(Duration delay)
```

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

### GetTimeRequest Implementation Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.naming/javax/naming/ldap/ExtendedRequest.html

Example implementation of the ExtendedRequest interface for a hypothetical 'get time' LDAP extended operation. This class handles the creation of the corresponding GetTimeResponse.

```Java
public class GetTimeRequest implements ExtendedRequest {
    public GetTimeRequest() {... };
    public ExtendedResponse createExtendedResponse(String id,
        byte[] berValue, int offset, int length)
        throws NamingException {
        return new GetTimeResponse(id, berValue, offset, length);
    }
    ... 
 }
```

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

### Example Usage

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.management/javax/management/StandardEmitterMBean.html

An example demonstrating how to create and register a StandardEmitterMBean that emits notifications.

```APIDOC
## Example Usage

The following example shows how to use the public constructor `StandardEmitterMBean(implementation, mbeanInterface, emitter)` to create an MBean emitting notifications with any implementation class name _Impl_ , with a management interface defined (as for current Standard MBeans) by any interface _Intf_ , and with any implementation of the interface `NotificationEmitter`. The example uses the class `NotificationBroadcasterSupport` as an implementation of the interface `NotificationEmitter`.

```java
     MBeanServer mbs;
     ... 
     final String[] types = new String[] {"sun.disc.space","sun.disc.alarm"};
     final MBeanNotificationInfo info = new MBeanNotificationInfo(
                                          types,
                                          Notification.class.getName(),
                                          "Notification about disc info.");
     final NotificationEmitter emitter = 
                    new NotificationBroadcasterSupport(info);

     final Intf impl = new Impl(...);
     final Object mbean = new StandardEmitterMBean(
                                     impl, Intf.class, emitter);
     mbs.registerMBean(mbean, objectName);
```
```

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

### Example Usage of resolve Method

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/module/Configuration.html

An example demonstrating how to use the `resolve` method to find modules and their dependencies, using the boot layer configuration as a parent.

```APIDOC
## Example

The following example uses the `resolve` method to resolve a module named _myapp_ with the configuration for the boot layer as the parent configuration. It prints the name of each resolved module and the names of the modules that each module reads.

```java
   Path dir1 = ..., dir2 = ..., dir3 = ...;
   ModuleFinder finder = ModuleFinder.of(dir1, dir2, dir3);
   Configuration parent = ModuleLayer.boot().configuration();
   Configuration cf = parent.resolve(finder, ModuleFinder.of(), Set.of("myapp"));
   cf.modules().forEach(m -> {
       System.out.format("%s -> %s%n",
           m.name(),
           m.reads().stream()
               .map(ResolvedModule::name)
               .collect(Collectors.joining(", "))));
   });
```
```

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

### Get Thread Start Requests

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jdi/com/sun/jdi/request/EventRequestManager.html

Returns an unmodifiable, live view of all enabled and disabled thread start requests. Changes to the request manager are reflected in this list.

```java
List<ThreadStartRequest> threadStartRequests()
```

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

### Create RecordingStream with Configuration

Source: https://docs.oracle.com/en/java/javase/24/docs/api/jdk.jfr/jdk/jfr/consumer/RecordingStream.html

Creates a recording stream using settings from a configuration. This example demonstrates using a predefined 'default' configuration.

```java
var c = Configuration.getConfiguration("default");
try (var rs = new RecordingStream(c)) {
    rs.onEvent(System.out::println);
    rs.start();
}
```

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

### Set Daylight Saving Time Start Rule (Detailed)

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/util/SimpleTimeZone.html

Sets the daylight saving time start rule, specifying month, day, day of week, and start time in local wall clock time. Example demonstrates setting DST to start on the first Sunday in April at 2 AM.

```java
setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY, 2*60*60*1000);
```

```java
public void setStartRule(int startMonth, int startDay, int startDayOfWeek, int startTime)
```

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

### Get Local Variable Type Start Scope

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/lang/classfile/class-use/Label.html

Returns the Label indicating the start of the scope for a LocalVariableType pseudo-instruction. This defines the range where the local variable type information is valid.

```java
Label LocalVariableType.startScope()
```

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

### Convenience Method Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/io/File.html

Demonstrates the usage of the convenience setExecutable method.

```java
file.setExecutable(arg, true)
```

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

### Example Configuration Entry

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/javax/security/auth/login/Configuration.html

Provides a concrete example of a Configuration entry for an application named 'Login', specifying required and optional LoginModules with options.

```plaintext
 Login {
   com.sun.security.auth.module.UnixLoginModule required;
   com.sun.security.auth.module.Krb5LoginModule optional
                   useTicketCache="true"
                   ticketCache="${user.home}${/}tickets";
 };
 
```

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

### Install Font Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.desktop/javax/swing/LookAndFeel.html

This snippet demonstrates how to install a font for a JComponent. It checks if the current font is null or a UIResource and, if so, retrieves the font from the UIManager defaults using a specified key.

```java
JComponent c;
Font font = c.getFont();
if (font == null || (font instanceof UIResource)) {
    c.setFont(UIManager.getFont("fontKey"));
}

```

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

### GetTimeResponse Implementation Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.naming/javax/naming/ldap/ExtendedRequest.html

Example implementation of the ExtendedResponse interface for a hypothetical 'get time' LDAP extended operation. This class decodes the response value and provides methods to retrieve the time.

```Java
public class GetTimeResponse implements ExtendedResponse {
    long time;
    public GetTimeResponse(String id, byte[] berValue, int offset,
        int length) throws NamingException {
        time =      ... // decode berValue to get time
    }
    public java.util.Date getDate() { return new java.util.Date(time) };
    public long getTime() { return time };
    ... 
 }
```

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

### Usage Example

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.base/java/nio/channels/spi/AbstractInterruptibleChannel.html

Illustrates the recommended usage pattern for `begin()` and `end()` methods within a try-finally block to ensure proper channel handling.

```APIDOC
## Usage Example

```java
boolean completed = false;
try {
    begin();
    completed = ...;    // Perform blocking I/O operation
    return ...;         // Return result
} finally {
    end(completed);
}
```
```

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

### Get Text Start Index

Source: https://docs.oracle.com/en/java/javase/24/docs/api/java.xml/javax/xml/stream/XMLStreamReader.html

Retrieves the starting offset of text characters within the character array for the current text event. This method is only valid for text states and may throw an IllegalStateException.

```java
int getTextStart()

```
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