Groovy example source code file (MetaClassTest.java)

This example Groovy source code file (MetaClassTest.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

arraylist, double, double, dymmyclass, dymmyclass, groovytestcase, integer, integer, iterator, metaclass, metaclass, metamethod, object, string, util

The Groovy MetaClassTest.java source code

/*
 * Copyright 2003-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package groovy.lang;

import groovy.util.GroovyTestCase;
import org.codehaus.groovy.runtime.InvokerHelper;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * @author <a href="mailto:james@coredevelopers.net">James Strachan
 * @version $Revision: 21515 $
 */
public class MetaClassTest extends GroovyTestCase {

    public void testMetaClass() {
        Class foo = String[].class;
        System.out.println(foo + " name: " + foo.getName());

        MetaClass metaClass = InvokerHelper.getMetaClass(this);

        assertTrue("got metaclass", metaClass != null);

        metaClass.invokeMethod(this, "doSomething", new Object[0]);
    }

    public void testArray() {
        String[] value = new String[]{"hello"};

        MetaClass metaClass = InvokerHelper.getMetaClass(value);

        assertTrue("got metaclass", metaClass != null);

        metaClass.invokeMethod(value, "toString", new Object[0]);
    }

    public void testString() {
        String value = "hello";

        MetaClass metaClass = InvokerHelper.getMetaClass(value);

        assertTrue("got metaclass", metaClass != null);

        Object answer = metaClass.invokeMethod(value, "toString", new Object[0]);

        assertEquals("hello", answer);
    }

    public void testObject() {
        Object value = new Object();

        MetaClass metaClass = InvokerHelper.getMetaClass(value);

        assertTrue("got metaclass", metaClass != null);

        metaClass.invokeMethod(value, "toString", new Object[0]);
    }

    public void testPublicField() {
        DymmyClass dymmyClass = new DymmyClass();

        MetaClass metaClass = InvokerHelper.getMetaClass(dymmyClass);

        assertEquals(metaClass.getProperty(dymmyClass, "x"), new Integer(0));
        assertEquals(metaClass.getProperty(dymmyClass, "y"), "none");

        metaClass.setProperty(dymmyClass, "x", new Integer(25));
        assertEquals(dymmyClass.x, 25);

        metaClass.setProperty(dymmyClass, "y", "newvalue");
        assertEquals(dymmyClass.y, "newvalue");
    }

    public void testSetPropertyWithInt() {
        DymmyClass dymmyClass = new DymmyClass();
        MetaClass metaClass = InvokerHelper.getMetaClass(dymmyClass);
        metaClass.setProperty(dymmyClass, "anInt", new Integer(10));
    }

    public void testSetPropertyWithDoubleArray() {
        DymmyClass dymmyClass = new DymmyClass();
        MetaClass metaClass = InvokerHelper.getMetaClass(dymmyClass);
        Double[][] matrix2 =
                {
                        {
                                new Double(35), new Double(50), new Double(120)
                        },
                        {
                                new Double(75), new Double(80), new Double(150)
                        }
                };
        metaClass.setProperty(dymmyClass, "matrix", matrix2);
        metaClass.setProperty(dymmyClass, "matrix2", matrix2);
    }

    public void testSetPropertyWithArray() {
        DymmyClass dymmyClass = new DymmyClass();
        MetaClass metaClass = InvokerHelper.getMetaClass(dymmyClass);

        // test int[]
        int[] ints = new int[]{
                0, 1, 2, 3
        };
        metaClass.setProperty(dymmyClass, "ints", ints);
        assertEquals(ints, metaClass.getProperty(dymmyClass, "ints"));

        // test Integer[]
        Integer[] integers = new Integer[]{
                new Integer(0), new Integer(1), new Integer(2), new Integer(3)
        };
        metaClass.setProperty(dymmyClass, "integers", integers);
        assertEquals(integers, metaClass.getProperty(dymmyClass, "integers"));
    }

    public void testSetPropertyWithList() {
        DymmyClass dymmyClass = new DymmyClass();
        MetaClass metaClass = InvokerHelper.getMetaClass(dymmyClass);

        // test list
        ArrayList list = new ArrayList();
        list.add(new Integer(120));
        list.add(new Integer(150));

        // test int[]
        metaClass.setProperty(dymmyClass, "ints", list);

        // test Integer[]
        metaClass.setProperty(dymmyClass, "integers", list);
    }

    public void testMetaMethodsOnlyAddedOnce() {
        MetaClass metaClass = InvokerHelper.getMetaClass("some String");

        List methods = metaClass.getMetaMethods();
        for (Iterator iter = methods.iterator(); iter.hasNext();) {
            MetaMethod method = (MetaMethod) iter.next();
            int count = 0;
            for (Iterator inner = methods.iterator(); inner.hasNext();) {
                MetaMethod runner = (MetaMethod) inner.next();
                if (method.equals(runner)) {
                    System.out.println("runner = " + runner);
                    System.out.println("method = " + method);
                    count++;
                }
            }
            assertEquals("count of Method " + method.getName(), 1, count);
        }

    }


    public void doSomething() {
        System.out.println("Called doSomething()");
    }
}


class DymmyClass {
    public int x = 0;
    public String y = "none";

    private int anInt;
    private int[] ints;
    private Integer[] integers;
    double[][] matrix2;
    Double[][] matrix;

    public Integer[] getIntegers() {
        return integers;
    }

    public void setIntegers(Integer[] integers) {
        this.integers = integers;
    }

    public int[] getInts() {
        return ints;
    }

    public void setInts(int[] ints) {
        this.ints = ints;
    }

    public int getAnInt() {
        return anInt;
    }

    public void setAnInt(int anInt) {
        this.anInt = anInt;
    }

    public void setMatrix(Double[][] matrix) {
        this.matrix = matrix;
    }

    public void setMatrix2(double[][] matrixReloaded) {
        this.matrix2 = matrixReloaded;
    }

}