Java 8

Java is a high-level, general-purpose, memory-safe, object-oriented programming language.

This is LiveCodes' Java 8 engine: source is compiled and run in the browser by a JDK 8 JVM interpreter. It runs classic Java, but it cannot compile modern Java source (records, var, text blocks, switch expressions).

The java-wasm engine (also selected by java) compiles modern Java to WebAssembly in the browser and is faster and much smaller. Use java-8 only when you need Java 8 behavior for language-level compatibility.

Usage

Demo:

show code

JS

import { createPlayground } from 'livecodes';

const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
createPlayground('#container', options);

TS

import { createPlayground, type EmbedOptions } from 'livecodes';

const options: EmbedOptions = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
createPlayground('#container', options);

React

import LiveCodes from 'livecodes/react';

export default function App() {
  const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
  return (<LiveCodes {...options} />);
}

Vue

<script setup>
import LiveCodes from "livecodes/vue";

const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
</script>
<template>
  <LiveCodes v-bind="options" />
</template>

Svelte

<script>
import LiveCodes from 'livecodes/svelte';

const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
</script>

<LiveCodes {...options} />

Solid

import LiveCodes from 'livecodes/solid';

export default function App() {
  const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
  return (<LiveCodes {...options} />);
}

Preact

import LiveCodes from 'livecodes/preact';

export default function App() {
  const options = {
  "config": {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  }
};
  return (<LiveCodes {...options} />);
}

Web Components

<live-codes></live-codes>

<script type="module">
  import "livecodes/web-components";

  const playground = document.querySelector("live-codes");
  playground.config = {
    "activeEditor": "script",
    "script": {
      "language": "java-8",
      "content": "public class Main {\n  public static void main(String[] args) {\n    System.out.println(\"Hello from Java 8\");\n  }\n}\n"
    },
    "mode": "simple",
    "editor": "auto",
    "tools": {
      "status": "full"
    }
  };
</script>

Communication with JavaScript

The Java code runs in the context of the result page. A few helper properties and methods are available in the browser global livecodes.java object:

• livecodes.java.input: the initial standard input that is passed to the Java code.
• livecodes.java.loaded: A promise that resolves when the Java environment is loaded.
• livecodes.java.output: the standard output.
• livecodes.java.error: the standard error.
• livecodes.java.exitCode: the exit code.
• livecodes.java.run: a function that runs the Java code with new input.

Language Info

Name

java-8 (alias: java8)

Extension

.java (the language itself is selected by name)

Editor

script

Compiler

DoppioJVM

Version

DoppioJVM: v0.5.0, which runs Java 8 JDK.

Code Formatting

Using @wasm-fmt/clang-format, applying Google's Java style guide.

Links

• Java
• DoppioJVM