### Deck Property Expression Counting Examples

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/Deck.adoc

These examples demonstrate how to define expressions for counting properties within a deck. The format is '<expression name> : <expression>'. These expressions are used to expose map-level properties based on the number of pieces that satisfy the condition.

```plaintext
battleships:BB=1
cruisers:{CA==1}
```

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

### Configure Dependent Projects with Vassal Maven Repository

Source: https://github.com/vassalengine/vassal/blob/master/developers-guide/developers-guide.adoc

Example XML configuration for Maven projects depending on Vassal. Ensure you use the correct Vassal version.

```xml
<project>
  <dependencies>
    <dependency>
      <groupId>org.vassalengine</groupId>
      <artifactId>vassal-app</artifactId>
      <version>3.4.1</version> <!--1-->
    </dependency>
  </dependencies>
  <repositories>
    <repository>
      <id>vassal-releases</id>
      <url>https://vassalengine.org/maven/</url>
    </repository>
  </repositories>
</project>
```

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

### Example Property Match Expressions

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionSumCount.adoc

Demonstrates the syntax for property match expressions within Sum and Count functions. These expressions must be enclosed in curly braces and double quotes, with internal double quotes escaped using \".

```beanshell
CountStack("{Strength>3}") +
CountStack("{StepCount < 2 && Army == \"Russian\"}")
```

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

### Substring from Start Index

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Extracts a portion of a string starting from a specified character index to the end.

```Vassal
Test.substring(1)
```

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

### Simulate HiDPI Display During Development

Source: https://context7.com/vassalengine/vassal/llms.txt

Run VASSAL with a system property to simulate a HiDPI display for development purposes.

```bash
# Simulate a HiDPI display during development
java -Dsun.java2d.uiScale=2 -jar vassal-app/target/Vengine.jar
```

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

### Old-Style Property Match Expression Example

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/PropertyMatchExpression.adoc

An example of an old-style property match expression. These expressions are not enclosed in curly braces and have a restricted syntax for compatibility with older VASSAL modules.

```plaintext
nation = "German"
```

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

### Clean Project Build

Source: https://github.com/vassalengine/vassal/blob/master/developers-guide/developers-guide.adoc

Use this make command to clean the project before building.

```bash
$ make clean
```

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

### Running VASSAL

Source: https://context7.com/vassalengine/vassal/llms.txt

Commands to build VASSAL, run the Player with a module, and run the Editor to design modules. Includes an option to simulate HiDPI displays.

```APIDOC
## Building and Running VASSAL

**Maven build with all checks skipped (fast local build)**

```bash
# Full build, skip tests and static analysis tools
./mvnw clean package \
  -DskipTests=true \
  -Dcheckstyle.skip=true \
  -Dspotbugs.skip=true \
  -Dmaven.javadoc.skip=true \
  -Dasciidoctor.skip=true \
  -Dclirr.skip=true

# Run the Player with a module
java -jar vassal-app/target/Vengine.jar /path/to/MyGame.vmod

# Run the Editor to design/edit a module
java -jar vassal-app/target/Vengine.jar --edit /path/to/MyGame.vmod

# Simulate a HiDPI display during development
java -Dsun.java2d.uiScale=2 -jar vassal-app/target/Vengine.jar
```
```

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

### Get String Length

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Returns the number of characters in a string. Use this to determine the size of a string property.

```vassal
LastZone.length()
```

```vassal
"Beach".length() = 5
```

```vassal
"".length = 0
```

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

### Compile only, skip tests and other plugins

Source: https://github.com/vassalengine/vassal/blob/master/developers-guide/developers-guide.adoc

Use this command to perform a clean build, package the application, and skip various plugins like tests, checkstyle, spotbugs, javadoc, asciidoctor, and clirr.

```bash
$ mvn clean package -DskipTests=true -Dcheckstyle.skip=true -Dspotbugs.skip=true -Dmaven.javadoc.skip=true -Dasciidoctor.skip=true -Dclirr.skip=true
```

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

### Initialize and Access BasicPiece Properties

Source: https://context7.com/vassalengine/vassal/llms.txt

Demonstrates how to create a BasicPiece instance and access its built-in properties, such as location and name. Use this for the fundamental representation of a game piece.

```java
import VASSAL.counters.BasicPiece;
import VASSAL.build.module.BasicCommandEncoder;

// Standard type string format: "piece;IMAGE_NAME;PIECE_NAME"
String typeString = BasicPiece.ID + "infantry.png;Infantry Unit";
BasicPiece bp = new BasicPiece(typeString, null);

// Key built-in property names exposed by BasicPiece
System.out.println(BasicPiece.LOCATION_NAME);   // "LocationName"
System.out.println(BasicPiece.CURRENT_MAP);      // "CurrentMap"
System.out.println(BasicPiece.CURRENT_BOARD);    // "CurrentBoard"
System.out.println(BasicPiece.CURRENT_ZONE);     // "CurrentZone"
System.out.println(BasicPiece.CURRENT_X);        // "CurrentX"
System.out.println(BasicPiece.CURRENT_Y);        // "CurrentY"
System.out.println(BasicPiece.OLD_LOCATION_NAME);// "OldLocationName"
System.out.println(BasicPiece.BASIC_NAME);       // "BasicName"
System.out.println(BasicPiece.PIECE_NAME);       // "PieceName"
System.out.println(BasicPiece.DECK_NAME);        // "DeckName"
System.out.println(BasicPiece.STACK_POS);        // "StackPos"
System.out.println(BasicPiece.STACK_SIZE);       // "StackSize"
System.out.println(BasicPiece.UNIQUE_ID);        // "UniqueID"
System.out.println(BasicPiece.CLICKED_X);        // "ClickedX" — position of last right-click
System.out.println(BasicPiece.CLICKED_Y);        // "ClickedY"

// Read location-related properties
Object locationName = bp.getProperty(BasicPiece.LOCATION_NAME);
Object oldLocation  = bp.getProperty(BasicPiece.OLD_LOCATION_NAME);
```

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

### Substring with Start and End Indices

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Extracts a portion of a string between two specified character indices. The end index is exclusive.

```Vassal
Test.substring(1, 3)
```

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

### Check if String Starts With Substring

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Returns true if the target string begins with the specified search string. Useful for prefix matching.

```vassal
GetProperty("Test-1").startsWith("ZZ")
```

```vassal
"ZZ-23".startsWith("ZZ") = true
```

```vassal
"ZY-23".startsWith("ZZ") = false
```

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

### Build and Use DynamicProperty Trait in Java

Source: https://context7.com/vassalengine/vassal/llms.txt

Demonstrates how to programmatically create a piece with a DynamicProperty trait, set its value, and send a network command. Use this for dynamic game state management.

```java
import VASSAL.counters.DynamicProperty;
import VASSAL.counters.BasicPiece;
import VASSAL.counters.Decorator;
import VASSAL.command.Command;
import VASSAL.command.ChangeTracker;

// --- Build a piece with a Dynamic Property trait in code ---
// Type string format: "PROP;<name>;<numeric?>;<min>;<max>;<wrap?>;<format>;<description>;<...commands>"
BasicPiece base = new BasicPiece("piece;tank.png;Tank", null);

// Wrap a DynamicProperty trait around it (named "Strength", numeric 0-10, no wrap)
DynamicProperty dpTrait = new DynamicProperty(
    "PROP;Strength;true;0;10;false;;Armor strength;", base);
// dpTrait is now the outermost piece

// Read the value
System.out.println(dpTrait.getProperty("Strength")); // "  (initial empty value)

// Programmatically set the value and generate a network Command
ChangeTracker tracker = new ChangeTracker(dpTrait);
dpTrait.setProperty("Strength", "7");
Command cmd = tracker.getChangeCommand();
GameModule.getGameModule().sendAndLog(cmd);
```

```java
import VASSAL.configure.Parameter;
import java.util.List;
List<Parameter> params = List.of(
    new Parameter("Strength", "7"),
    new Parameter("Morale",   "4")
);
Command bulkCmd = Decorator.setDynamicProperties(params, dpTrait, propertySource, ownerAuditable);
GameModule.getGameModule().sendAndLog(bulkCmd);
```

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

### Build VASSAL with Maven (Skip Checks)

Source: https://context7.com/vassalengine/vassal/llms.txt

Use this command for a fast local build of VASSAL, skipping tests and static analysis tools.

```bash
# Full build, skip tests and static analysis tools
./mvnw clean package \
  -DskipTests=true \
  -Dcheckstyle.skip=true \
  -Dspotbugs.skip=true \
  -Dmaven.javadoc.skip=true \
  -Dasciidoctor.skip=true \
  -Dclirr.skip=true
```

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

### Get and Set Global Property Values

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/GlobalProperties.adoc

Use these methods to retrieve the current value of a global property or to assign a new value to it.

```Java
property.getPropertyValue()
```

```Java
property.setPropertyValue()
```

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

### BeanShell Property Match Expression Examples

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/PropertyMatchExpression.adoc

BeanShell Property Match Expressions leverage the full BeanShell language for complex conditions. They are enclosed in curly braces.

```beanshell
{MaxHeight < (CurrentHeight + Growth) && Age > $myAge$}
```

```beanshell
{Nation == (unitType=="Infantry" ? unitNation : formationNation)}
```

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

### Run VASSAL Editor to Design/Edit a Module

Source: https://context7.com/vassalengine/vassal/llms.txt

Launch the VASSAL Editor to create or modify a game module.

```bash
# Run the Editor to design/edit a module
java -jar vassal-app/target/Vengine.jar --edit /path/to/MyGame.vmod
```

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

### BeanShell Expression - Logical Operations

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/Expression.adoc

Provides examples of logical operators (AND, OR, NOT) and grouping in BeanShell expressions. These are commonly used in property match expressions and conditional logic.

```beanshell
{Nation=="Germany" && Type == "Unit"}
```

```beanshell
{Nation == "Germany" || Type == "Unit"}
```

```beanshell
{!isInUse}
```

```beanshell
{A==B && (C == 1 || D == 2)}
```

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

### Run VASSAL Player with a Module

Source: https://context7.com/vassalengine/vassal/llms.txt

Execute the VASSAL Player application with a specified game module.

```bash
# Run the Player with a module
java -jar vassal-app/target/Vengine.jar /path/to/MyGame.vmod
```

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

### Configure OpenGL for Graphics

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/userguide/userguide.adoc

Add these VM flags to the vassal.vmoptions file to potentially resolve map tearing or graphics corruption issues on non-Windows platforms. Try them one at a time.

```properties
-Dsun.java2d.opengl=true
```

```properties
-Dsun.java2d.opengl=false
```

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

### Create New Branch for FlatPak Release

Source: https://github.com/vassalengine/vassal/blob/master/developers-guide/developers-guide.adoc

Create and checkout a new branch for the FlatPak release.

```bash
cd org.vassalengine.vassal
git checkout -b release-x.y.z
```

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

### Ternary Operator Example

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/Expression.adoc

The ternary operator provides a concise way to express conditional logic, returning one of two values based on a boolean expression.

```Vassal Expression
{A == B ? C : D}
```

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

### Find Last Occurrence of Substring

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Searches for the last occurrence of a substring and returns its starting index (0-based). Returns -1 if the substring is not found. Useful for finding the final instance of a pattern.

```vassal
Test.lastIndexOf("-")
```

```vassal
"23-ZZ-23".lastIndexOf("23") = 6
```

```vassal
"ZZ-23".lastIndexOf("ZZ") = 0
```

```vassal
"abcdefa".lastIndexOf("A") = -1
```

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

### VASSAL.tools.logging.LogEntry Fields and Constructors

Source: https://github.com/vassalengine/vassal/blob/master/vassal-app/src/test/resources/depreport/deprecated.txt

Represents a single log entry with severity, message, and other details.

```APIDOC
## VASSAL.tools.logging.LogEntry

### Description
Represents a structured log message, containing information about its type, timestamp, process ID, and the message content.

### Constructors
- `LogEntry(int type, int pid, java.lang.Throwable throwable, java.lang.String message, boolean flush)`: Constructs a log entry with detailed information.
- `LogEntry(long timestamp, int type, int pid, java.lang.Throwable throwable, java.lang.String message, boolean flush)`: Constructs a log entry with a specified timestamp.

### Fields
- `BUG`: Constant for bug log type.
- `DEBUG`: Constant for debug log type.
- `ERROR`: Constant for error log type.
- `MESSAGE`: Constant for general message log type.
- `SYSTEM`: Constant for system log type.
- `WARNING`: Constant for warning log type.
- `message`: The log message string.
- `pid`: The process ID associated with the log entry.
- `serialVersionUID`: Serial version UID for serialization.
- `timestamp`: The time the log entry was created.
- `trace`: The throwable associated with the log entry.
- `type`: The type or severity of the log entry.

### Methods
- `toString()`: Returns a string representation of the log entry.
- `wait`: (Note: This field seems out of place for a LogEntry, likely a typo or internal detail not meant for public API documentation).
```

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

### Find First Occurrence of Substring

Source: https://github.com/vassalengine/vassal/blob/master/vassal-doc/src/main/readme-referencemanual/ReferenceManual/ExpressionString.adoc

Searches for the first occurrence of a substring and returns its starting index (0-based). Returns -1 if the substring is not found. Useful for locating specific parts of a string.

```vassal
{ Test.indexOf("zone") < 0 ? "Not Found" : "Found" }
```

```vassal
"ZZ-23".indexOf("ZZ") = 0
```

```vassal
"ZY-23".indexOf("ZZ") = -1
```

```vassal
"ZY-23-Y2".indexOf("Y") = 1
```