CompileString.java Source code

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Here is the source code for CompileString.java

Source

import java.lang.reflect.Method;
import java.net.URI;
import java.util.Iterator;
import java.util.NoSuchElementException;

import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.ToolProvider;

public class CompileString {
    public static void main(String[] args) throws Exception {
        JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
        String program = "class Test{" + "   public static void main (String [] args){"
                + "      System.out.println (\"Hello, World\");" + "      System.out.println (args.length);"
                + "   }" + "}";

        Iterable<? extends JavaFileObject> fileObjects;
        fileObjects = getJavaSourceFromString(program);

        compiler.getTask(null, null, null, null, null, fileObjects).call();

        Class<?> clazz = Class.forName("Test");
        Method m = clazz.getMethod("main", new Class[] { String[].class });
        Object[] _args = new Object[] { new String[0] };
        m.invoke(null, _args);
    }

    static Iterable<JavaSourceFromString> getJavaSourceFromString(String code) {
        final JavaSourceFromString jsfs;
        jsfs = new JavaSourceFromString("code", code);
        return new Iterable<JavaSourceFromString>() {
            public Iterator<JavaSourceFromString> iterator() {
                return new Iterator<JavaSourceFromString>() {
                    boolean isNext = true;

                    public boolean hasNext() {
                        return isNext;
                    }

                    public JavaSourceFromString next() {
                        if (!isNext)
                            throw new NoSuchElementException();
                        isNext = false;
                        return jsfs;
                    }

                    public void remove() {
                        throw new UnsupportedOperationException();
                    }
                };
            }
        };
    }
}

class JavaSourceFromString extends SimpleJavaFileObject {
    final String code;

    JavaSourceFromString(String name, String code) {
        super(URI.create("string:///" + name.replace('.', '/') + Kind.SOURCE.extension), Kind.SOURCE);
        this.code = code;
    }

    public CharSequence getCharContent(boolean ignoreEncodingErrors) {
        return code;
    }
}