Java by API/javax.script/ScriptEngine

ScriptEngine: eval(Reader reader)

  
import java.io.FileReader;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
public class Main {
  public static void main(String[] args) {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    try {
      FileReader reader = new FileReader("yourFile.js");
      engine.eval(reader);
      reader.close();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

ScriptEngine: eval(String script)

  
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
public class Main {
  public static void main(String[] args) {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    String script = "print ("www.jexp.ru")";
    try {
      engine.eval(script);
    } catch (ScriptException e) {
      e.printStackTrace();
    }
  }
}

ScriptEngine: getBindings(int scope)

  
import javax.script.Bindings;
import javax.script.ScriptContext;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
public class Main {
  public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    engine.put("a", 1);
    engine.put("b", 5);
    Bindings bindings = engine.getBindings(ScriptContext.ENGINE_SCOPE);
    Object a = bindings.get("a");
    Object b = bindings.get("b");
    System.out.println("a = " + a);
    System.out.println("b = " + b);
    Object result = engine.eval("c = a + b;");
    System.out.println("a + b = " + result);
  }
}

ScriptEngine: get(String key)

  
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
public class Main {
  public static void main(String args[]) {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("javascript");
    try {
      engine.put("name", "abcde");
      engine.eval("var output = "";for (i = 0; i <= name.length; i++) {"
          + "  output = name.charAt(i)+"-" + output" + "}");
      String name = (String) engine.get("output");
      System.out.println(name);
    } catch (ScriptException e) {
      System.err.println(e);
    }
  }
}

ScriptEngine: put(String key, Object value)

  

import javax.script.Bindings;
import javax.script.ScriptContext;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
public class Main {
  public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    engine.put("a", 1);
    engine.put("b", 5);
    Bindings bindings = engine.getBindings(ScriptContext.ENGINE_SCOPE);
    Object a = bindings.get("a");
    Object b = bindings.get("b");
    System.out.println("a = " + a);
    System.out.println("b = " + b);
    Object result = engine.eval("c = a + b;");
    System.out.println("a + b = " + result);
  }
}