adityapawade / java_on_script

Java on script

Java on Script

Simple scripting library for Java programs

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Features

• Simple scripting syntax with support for nested blocks, for loops, if conditions
• Support for adding custom function implementations

Maven configuration

JoS is available on Maven Central. You just have to add the following dependency in your pom.xml file.

<dependency>
  <groupId>com.adtsw.jos</groupId>
  <artifactId>dsl</artifactId>
  <version>1.0.12</version>
</dependency>

For snapshots, add the following repository to your pom.xml file.

<repository>
    <id>sonatype snapshots</id>
    <url>https://oss.sonatype.org/content/repositories/snapshots</url>
</repository>

The snapshot version has not been released yet.

<dependency>
  <groupId>com.adtsw.jos</groupId>
  <artifactId>dsl</artifactId>
  <version>TBD</version>
</dependency>

Sample Script

    // init variables
    test_variable = 14;
    test_variable_expression = test_variable * 2;
    test_diff = 0.0;
    
    // conditions
    if(test_variable != 0) {
        
        test_diff = ((test_variable * 1.0) / (test_variable_expression * 1.0)) * 100.0;
        
        // logging
        log("test diff");
        log(test_diff);

        // nested conditions
        if(test_diff == 50.0) {
            log("value matches. updating original value");
            test_diff = test_diff + 50.0;
        }
    }

    // for loops
    for_loop_value = 0;
    
    for(i=0, i<test_variable_expression, i=i+1) {
        if(i % 2 == 0) {
            for_loop_value = for_loop_value + 1;
        }
    }

    // support for custom UDFs
    udf_value = custom_udf(var_1: test_variable, var_2: test_variable_expression);

    log("udf value");
    log(udf_value);

Usage

    public static void main(String[] args) {
        
        ScriptCompiler compiler = new ScriptCompiler("basic_udf", "examples/src/main/resources", new HashMap<>());
        ScriptContext scriptContext = compiler.compile();
        ScriptRunner scriptRunner = new ScriptRunner(scriptContext, new ScriptInput(new HashMap<>()), new HashMap<>(){{
            put("custom_udf", new AbstractFunctionDefinition() {
                @Override
                public void execute(ScriptLineContext lineContext, ScriptRuntimeContext runtimeContext) {
                    FunctionContext functionContext = lineContext.getFunctionContext();
                    String variableName = lineContext.getVariableContext().getName();
                    Integer var1 = (Integer) getArgValue(functionContext, runtimeContext, 0);
                    Integer var2 = (Integer) getArgValue(functionContext, runtimeContext, 1);
                    runtimeContext.getRunTimeVariables().put(variableName, var1 + var2);
                }
            });
        }});
        scriptRunner.run();
        Object udf_value = scriptRunner.getRuntimeContext().getRunTimeVariables().get("udf_value");
        System.out.println("value accessed from code : " + udf_value);
    }