TeaVM Documentation

If you prefer not to use Maven, you can embed TeaVM directly into your application or create custom plugins for build tools like Ant or Gradle.

Warning: These embedding APIs are considered unstable and may change between versions.

Key entry points:

• org.teavm.tooling.TeaVMTool (from teavm-tooling artifact): The primary starting point for embedding.
• org.teavm.vm.TeaVM (from teavm-core artifact): For deeper integration; review how TeaVMTool initializes this class to understand its usage.

After building a sample, you can quickly test the resulting WAR file using the following Gradle tasks depending on your operating system:

• Unix/macOS: ./gradlew :<example-name>:appRunWar
• Windows: gradlew bat :<example-name>:appRunWar

Replace <example-name> with the actual name of the example you wish to run.

To build the samples in this repository, you have two options:

1. Preferred Method: Publish TeaVM to your local repository following the instructions in the main README.
2. Manual Method: Use the provided build.gradle.kts and update the TeaVM version to the most recent version available on Maven Central. You can find the current version number on the badge in the main README.

Note: Some examples provide native binaries; check the specific build files for those examples.

To build TeaVM from the source code, clone the repository and use the Gradle wrapper to publish to your local Maven repository.

Note: Samples must be built separately following the instructions in samples/README.md.

git clone https://github.com/konsoletyper/teavm.git
./gradlew publishToMavenLocal

To compare the execution speed of JavaScript produced by TeaVM and GWT using the JBox2D CPU-intensive computation benchmark, use the following Gradle command to start the web application:

$ gradle appStartWar

On Linux, you can build and run the benchmark as a native executable using the following Gradle command. Note that you must install the required system dependencies (cmake and gtk-devel) via your Linux distribution's package manager before running this.

$ gradle runNativeLinux

The TeaVM CLI allows you to compile Java classes into target languages like JavaScript, WebAssembly (Wasm-GC), or C. The basic usage pattern is to provide the main class as a positional argument followed by optional configuration flags.

Basic Syntax: java org.teavm.cli.TeaVMRunner [OPTIONS] [qualified.main.Class]

The TAbstractStringBuilder class supports appending and inserting a wide range of data types, including:

• Object (via String.valueOf(obj))
• String and CharSequence
• int, long, float, double (with support for radix in integer methods)
• boolean ("true" or "false")
• char and int (as code points)
• char[] arrays

Use the following methods to manipulate the character sequence:

• delete(int start, int end): Removes the subsequence in the specified range.
• deleteCharAt(int index): Removes the character at the specified index.
• replace(int start, int end, TString str): Replaces the subsequence in the specified range with the given TString.
• reverse(): Reverses the character sequence.
• setCharAt(int index, char ch): Replaces the character at the specified index with the specified character.

Use indexOf and lastIndexOf to find the index of a TString within the builder.

• indexOf(TString str): Returns the first index of the specified substring, or -1 if not found.
• indexOf(TString str, int fromIndex): Returns the first index of the specified substring, starting at the specified index.
• lastIndexOf(TString str): Returns the last index of the specified substring, or -1 if not found.
• lastIndexOf(TString str, int fromIndex): Returns the last index of the specified substring, searching backward starting from the specified index.