Java

老猫10/22/22About 4 min

globals Java

Global utilities for loading classes, constructing instances, boxing primitives, and bridging callbacks between Java and the script thread.

Methods

boxBoolean
boxByte
boxChar
boxDouble
boxFloat
boxInt
boxLong
boxShort
create
createSync
defineClass
findClass
findClassOrNull
loadDex
loadJar
setDefaultThreadMode
setThreadMode
wrap

Methods

boxByte

boxByte(value: number): any

Boxes value as java.lang.Byte for disambiguating overloaded methods (byte vs java.lang.Byte).

Example

"nodejs";
require('rhino').install();
const $java = $autojs.java;

const values = new android.content.ContentValues();
values.put("key", $java.boxByte(1));

Name	Type	Default	Description
`constructor`	`any`	—	Java class constructor function. Throws `TypeError` if not a Java constructor.
`args`	`any[]`	—	Arguments passed to the Java constructor.
`threadMode?`	`ThreadMode`	`'current'`	Thread used to run the constructor.

Name	Type	Default	Description
`constructor`	`any`	—	Java class constructor function. Throws `TypeError` if invalid.
`args`	`any[]`	—	Constructor arguments.
`threadMode?`	`ThreadMode`	`'current'`	Thread for construction.

defineClass

defineClass(jsClass, options?): Promise<C>

Generates a Java class from a JavaScript class that extends a Java type and/or implements Java interfaces—useful for abstract base classes or overriding methods such as WebViewClient.shouldOverrideUrlLoading.

Implementation builds DEX on demand (can be slow the first time; subsequent calls may reuse cached DEX). By default the cache file lives under .codecache in the current working directory; configure paths via DefineClassOptions.

If you only need a single Java interface, you can often use new SomeInterface({ ... }) instead of defineClass.

Example

"nodejs";
require('rhino').install();
const $java = $autojs.java;

async function main() {
  const MyWebViewClient = await $java.defineClass(
     class MyWebViewClient extends android.webkit.WebViewClient {
         shouldOverrideUrlLoading(webview, url) {
              if (typeof(url) === 'string') {
                  console.log(url);
              }
              return false;
         }
    }
  );
  const client = new MyWebViewClient();
}
main().catch(console.error);

Parameters

Name	Type	Description
`jsClass`	`C`	JavaScript class inheriting Java types / implementing interfaces.
`options?`	`DefineClassOptions`	Package name, interfaces, DEX cache path, etc.

Returns

Promise<C>

findClass

findClass(name: string): any

Loads the class named name and returns its Java-side constructor (a JavaScript-callable function). You can new it for instances or call static methods on it.

Inner classes use $ in the name, e.g. android.app.AlertDialog$Builder.

Throws ClassNotFoundError if the class cannot be loaded.

Example

"nodejs";
const $java = $autojs.java;
const Integer = $java.findClass('java.lang.Integer');
const int = new Integer(255);
console.log(Integer.toHexString(int));

Parameters

name: string — fully qualified Java class name.

Returns

any — the Java class / constructor function.

findClassOrNull

findClassOrNull(name: string): any

Same as findClass, but returns null if the class is missing instead of throwing.

See also: findClass

Parameters

name: string

Returns

any — Java class or null.

loadDex

loadDex(dexFile: string): Promise<void>

Loads a .dex file asynchronously. Classes from that DEX become available to JavaScript after the promise settles.

Always await completion before constructing types from that DEX.

Example

"nodejs";
const $java = $autojs.java;
require('rhino').install();

async function main() {
   await $java.loadDex('/sdcard/mydex.dex');
   console.log(new com.example.MyClass());
}
main().catch(console.error);

Parameters

dexFile: string — absolute path to the .dex file.

Returns

Promise<void>

loadJar

loadJar(jarFile: string): Promise<void>

Loads a .jar similarly to loadDex: the runtime typically converts the JAR to DEX internally, so unsupported bytecode or API mismatches can fail. When possible, pre-convert to DEX for faster, more reliable loads.

Example

"nodejs";
const $java = $autojs.java;
require('rhino').install();

async function main() {
   await $java.loadJar('/sdcard/myjar.jar');
   console.log(new com.example.MyClass());
}
main().catch(console.error);

Parameters

jarFile: string — path to the .jar file.

Returns

Promise<void>

setDefaultThreadMode

setDefaultThreadMode(clazz: any, threadMode: ThreadMode): any

Sets the default ThreadMode for new instances of clazz. Existing instances are unchanged.

Example

"nodejs";
const $java = $autojs.java;
const View = $java.findClass('android.view.View');
$java.setDefaultThreadMode(View, 'ui');

Parameters

Name	Type	Description
`clazz`	`any`	Java class object returned by `findClass`.
`threadMode`	`ThreadMode`	Default thread for future instances.

Returns

any

setThreadMode

setThreadMode(obj: any, threadMode: ThreadMode): any

Pins obj to a thread. Subsequent method calls marshal to that thread; if not on the current thread, marshaled calls resolve to Promises.

Example

"nodejs";
const $java = $autojs.java;
const TextView = $java.findClass('android.widget.TextView');
(async () => {
    const textView = await $java.create(TextView, [$autojs.androidContext], 'ui');
    $java.setThreadMode(textView, 'ui');
    await textView.setText('Hello World');
})();

Parameters

Name	Type	Description
`obj`	`any`	Java object wrapper.
`threadMode`	`ThreadMode`	Thread to execute calls on.

Returns

any

wrap

wrap<T>(obj: T, sync?: boolean): T

Wraps a JavaScript object (function or interface-shaped object) so that when Java invokes it from another thread, execution jumps back to the script thread. If sync === true, Java blocks until the script thread returns a value.

Typical use: Android listeners invoked on non-script threads.

Example

"nodejs";
const $java = $autojs.java;
const Button = $java.findClass('android.widget.Button');
(async () => {
    const button = await $java.create(Button, [$autojs.androidContext], 'ui');
    $java.setThreadMode(button, 'ui');
    button.setOnClickListener($java.wrap(() => {
       console.log('click');
    }));
    button.setOnLongClickListener($java.wrap({
         onLongClick: () => {
            console.log('long click');
            return true;
         },
    }, true));
})();

Type parameters

Name
`T`

Parameters

Name	Type	Default	Description
`obj`	`T`	—	Listener function or object with interface methods.
`sync?`	`boolean`	`false`	When `true`, block the Java caller until the script completes.

Returns

T