Java example source code file (ClassUtilsTest.java)

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Java - Java tags/keywords

class, classnotfoundexception, classutils, entry, exception, inner, list, method, named, object, reflection, string, test, util, wrong

The ClassUtilsTest.java Java example source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.commons.lang3;

import static org.apache.commons.lang3.JavaVersion.JAVA_1_5;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNotSame;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.commons.lang3.ClassUtils.Interfaces;
import org.apache.commons.lang3.reflect.testbed.GenericConsumer;
import org.apache.commons.lang3.reflect.testbed.GenericParent;
import org.apache.commons.lang3.reflect.testbed.StringParameterizedChild;
import org.junit.Test;

/**
 * Unit tests {@link org.apache.commons.lang3.ClassUtils}.
 */
@SuppressWarnings("boxing") // JUnit4 does not support primitive equality testing apart from long
public class ClassUtilsTest  {

    private static class Inner {
        private class DeeplyNested{}
    }

    //-----------------------------------------------------------------------
    @Test
    public void testConstructor() {
        assertNotNull(new ClassUtils());
        final Constructor<?>[] cons = ClassUtils.class.getDeclaredConstructors();
        assertEquals(1, cons.length);
        assertTrue(Modifier.isPublic(cons[0].getModifiers()));
        assertTrue(Modifier.isPublic(ClassUtils.class.getModifiers()));
        assertFalse(Modifier.isFinal(ClassUtils.class.getModifiers()));
    }

    // -------------------------------------------------------------------------
    @Test
    public void test_getShortClassName_Object() {
        assertEquals("ClassUtils", ClassUtils.getShortClassName(new ClassUtils(), "<null>"));
        assertEquals("ClassUtilsTest.Inner", ClassUtils.getShortClassName(new Inner(), "<null>"));
        assertEquals("String", ClassUtils.getShortClassName("hello", "<null>"));
        assertEquals("<null>", ClassUtils.getShortClassName(null, ""));

        // Inner types
        class Named {}
        assertEquals("ClassUtilsTest.1", ClassUtils.getShortClassName(new Object(){}, "<null>"));
        assertEquals("ClassUtilsTest.1Named", ClassUtils.getShortClassName(new Named(), "<null>"));
        assertEquals("ClassUtilsTest.Inner", ClassUtils.getShortClassName(new Inner(), "<null>"));
    }

    @Test
    public void test_getShortClassName_Class() {
        assertEquals("ClassUtils", ClassUtils.getShortClassName(ClassUtils.class));
        assertEquals("Map.Entry", ClassUtils.getShortClassName(Map.Entry.class));
        assertEquals("", ClassUtils.getShortClassName((Class<?>) null));

        // LANG-535
        assertEquals("String[]", ClassUtils.getShortClassName(String[].class));
        assertEquals("Map.Entry[]", ClassUtils.getShortClassName(Map.Entry[].class));

        // Primitives
        assertEquals("boolean", ClassUtils.getShortClassName(boolean.class));
        assertEquals("byte", ClassUtils.getShortClassName(byte.class));
        assertEquals("char", ClassUtils.getShortClassName(char.class));
        assertEquals("short", ClassUtils.getShortClassName(short.class));
        assertEquals("int", ClassUtils.getShortClassName(int.class));
        assertEquals("long", ClassUtils.getShortClassName(long.class));
        assertEquals("float", ClassUtils.getShortClassName(float.class));
        assertEquals("double", ClassUtils.getShortClassName(double.class));

        // Primitive Arrays
        assertEquals("boolean[]", ClassUtils.getShortClassName(boolean[].class));
        assertEquals("byte[]", ClassUtils.getShortClassName(byte[].class));
        assertEquals("char[]", ClassUtils.getShortClassName(char[].class));
        assertEquals("short[]", ClassUtils.getShortClassName(short[].class));
        assertEquals("int[]", ClassUtils.getShortClassName(int[].class));
        assertEquals("long[]", ClassUtils.getShortClassName(long[].class));
        assertEquals("float[]", ClassUtils.getShortClassName(float[].class));
        assertEquals("double[]", ClassUtils.getShortClassName(double[].class));

        // Arrays of arrays of ...
        assertEquals("String[][]", ClassUtils.getShortClassName(String[][].class));
        assertEquals("String[][][]", ClassUtils.getShortClassName(String[][][].class));
        assertEquals("String[][][][]", ClassUtils.getShortClassName(String[][][][].class));
        
        // Inner types
        class Named {}
        assertEquals("ClassUtilsTest.2", ClassUtils.getShortClassName(new Object(){}.getClass()));
        assertEquals("ClassUtilsTest.2Named", ClassUtils.getShortClassName(Named.class));
        assertEquals("ClassUtilsTest.Inner", ClassUtils.getShortClassName(Inner.class));
    }



    @Test
    public void test_getShortClassName_String() {
        assertEquals("ClassUtils", ClassUtils.getShortClassName(ClassUtils.class.getName()));
        assertEquals("Map.Entry", ClassUtils.getShortClassName(Map.Entry.class.getName()));
        assertEquals("", ClassUtils.getShortClassName((String) null));
        assertEquals("", ClassUtils.getShortClassName(""));
    }

    @Test
    public void test_getSimpleName_Class() {
        assertEquals("ClassUtils", ClassUtils.getSimpleName(ClassUtils.class));
        assertEquals("Entry", ClassUtils.getSimpleName(Map.Entry.class));
        assertEquals("", ClassUtils.getSimpleName((Class<?>) null));

        // LANG-535
        assertEquals("String[]", ClassUtils.getSimpleName(String[].class));
        assertEquals("Entry[]", ClassUtils.getSimpleName(Map.Entry[].class));

        // Primitives
        assertEquals("boolean", ClassUtils.getSimpleName(boolean.class));
        assertEquals("byte", ClassUtils.getSimpleName(byte.class));
        assertEquals("char", ClassUtils.getSimpleName(char.class));
        assertEquals("short", ClassUtils.getSimpleName(short.class));
        assertEquals("int", ClassUtils.getSimpleName(int.class));
        assertEquals("long", ClassUtils.getSimpleName(long.class));
        assertEquals("float", ClassUtils.getSimpleName(float.class));
        assertEquals("double", ClassUtils.getSimpleName(double.class));

        // Primitive Arrays
        assertEquals("boolean[]", ClassUtils.getSimpleName(boolean[].class));
        assertEquals("byte[]", ClassUtils.getSimpleName(byte[].class));
        assertEquals("char[]", ClassUtils.getSimpleName(char[].class));
        assertEquals("short[]", ClassUtils.getSimpleName(short[].class));
        assertEquals("int[]", ClassUtils.getSimpleName(int[].class));
        assertEquals("long[]", ClassUtils.getSimpleName(long[].class));
        assertEquals("float[]", ClassUtils.getSimpleName(float[].class));
        assertEquals("double[]", ClassUtils.getSimpleName(double[].class));

        // Arrays of arrays of ...
        assertEquals("String[][]", ClassUtils.getSimpleName(String[][].class));
        assertEquals("String[][][]", ClassUtils.getSimpleName(String[][][].class));
        assertEquals("String[][][][]", ClassUtils.getSimpleName(String[][][][].class));
        
        // On-the-fly types
        class Named {}
        assertEquals("", ClassUtils.getSimpleName(new Object(){}.getClass()));
        assertEquals("Named", ClassUtils.getSimpleName(Named.class));
    }

    @Test
    public void test_getSimpleName_Object() {
        assertEquals("ClassUtils", ClassUtils.getSimpleName(new ClassUtils(), "<null>"));
        assertEquals("Inner", ClassUtils.getSimpleName(new Inner(), "<null>"));
        assertEquals("String", ClassUtils.getSimpleName("hello", "<null>"));
        assertEquals("<null>", ClassUtils.getSimpleName(null, ""));
    }

    // -------------------------------------------------------------------------
    @Test
    public void test_getPackageName_Object() {
        assertEquals("org.apache.commons.lang3", ClassUtils.getPackageName(new ClassUtils(), "<null>"));
        assertEquals("org.apache.commons.lang3", ClassUtils.getPackageName(new Inner(), "<null>"));
        assertEquals("<null>", ClassUtils.getPackageName(null, ""));
    }

    @Test
    public void test_getPackageName_Class() {
        assertEquals("java.lang", ClassUtils.getPackageName(String.class));
        assertEquals("java.util", ClassUtils.getPackageName(Map.Entry.class));
        assertEquals("", ClassUtils.getPackageName((Class<?>) null));

        // LANG-535
        assertEquals("java.lang", ClassUtils.getPackageName(String[].class));

        // Primitive Arrays
        assertEquals("", ClassUtils.getPackageName(boolean[].class));
        assertEquals("", ClassUtils.getPackageName(byte[].class));
        assertEquals("", ClassUtils.getPackageName(char[].class));
        assertEquals("", ClassUtils.getPackageName(short[].class));
        assertEquals("", ClassUtils.getPackageName(int[].class));
        assertEquals("", ClassUtils.getPackageName(long[].class));
        assertEquals("", ClassUtils.getPackageName(float[].class));
        assertEquals("", ClassUtils.getPackageName(double[].class));

        // Arrays of arrays of ...
        assertEquals("java.lang", ClassUtils.getPackageName(String[][].class));
        assertEquals("java.lang", ClassUtils.getPackageName(String[][][].class));
        assertEquals("java.lang", ClassUtils.getPackageName(String[][][][].class));
        
        // On-the-fly types
        class Named {}
        assertEquals("org.apache.commons.lang3", ClassUtils.getPackageName(new Object() {
        }.getClass()));
        assertEquals("org.apache.commons.lang3", ClassUtils.getPackageName(Named.class));
    }

    @Test
    public void test_getPackageName_String() {
        assertEquals("org.apache.commons.lang3", ClassUtils.getPackageName(ClassUtils.class.getName()));
        assertEquals("java.util", ClassUtils.getPackageName(Map.Entry.class.getName()));
        assertEquals("", ClassUtils.getPackageName((String) null));
        assertEquals("", ClassUtils.getPackageName(""));
    }

    // -------------------------------------------------------------------------
    @Test
    public void test_getAbbreviatedName_Class() {
        assertEquals("", ClassUtils.getAbbreviatedName((Class<?>)null, 1));
        assertEquals("j.l.String", ClassUtils.getAbbreviatedName(String.class, 1));
        assertEquals("j.l.String", ClassUtils.getAbbreviatedName(String.class, 5));
        assertEquals("j.lang.String", ClassUtils.getAbbreviatedName(String.class, 13));
        assertEquals("j.lang.String", ClassUtils.getAbbreviatedName(String.class, 15));
        assertEquals("java.lang.String", ClassUtils.getAbbreviatedName(String.class, 20));
    }

    @Test(expected = IllegalArgumentException.class)
    public void test_getAbbreviatedName_Class_ZeroLen() {
        ClassUtils.getAbbreviatedName(String.class, 0);
    }

    @Test(expected = IllegalArgumentException.class)
    public void test_getAbbreviatedName_Class_NegativeLen() {
        ClassUtils.getAbbreviatedName(String.class, -10);
    }

    @Test
    public void test_getAbbreviatedName_String() {
        assertEquals("", ClassUtils.getAbbreviatedName((String) null, 1));
        assertEquals("WithoutPackage", ClassUtils.getAbbreviatedName("WithoutPackage", 1));
        assertEquals("j.l.String", ClassUtils.getAbbreviatedName("java.lang.String", 1));
    }

    // -------------------------------------------------------------------------
    @Test
    public void test_getAllSuperclasses_Class() {
        final List<?> list = ClassUtils.getAllSuperclasses(CY.class);
        assertEquals(2, list.size());
        assertEquals(CX.class, list.get(0));
        assertEquals(Object.class, list.get(1));

        assertEquals(null, ClassUtils.getAllSuperclasses(null));
    }

    @Test
    public void test_getAllInterfaces_Class() {
        final List<?> list = ClassUtils.getAllInterfaces(CY.class);
        assertEquals(6, list.size());
        assertEquals(IB.class, list.get(0));
        assertEquals(IC.class, list.get(1));
        assertEquals(ID.class, list.get(2));
        assertEquals(IE.class, list.get(3));
        assertEquals(IF.class, list.get(4));
        assertEquals(IA.class, list.get(5));

        assertEquals(null, ClassUtils.getAllInterfaces(null));
    }

    private static interface IA {
    }
    private static interface IB {
    }
    private static interface IC extends ID, IE {
    }
    private static interface ID {
    }
    private static interface IE extends IF {
    }
    private static interface IF {
    }
    private static class CX implements IB, IA, IE {
    }
    private static class CY extends CX implements IB, IC {
    }

    // -------------------------------------------------------------------------
    @Test
    public void test_convertClassNamesToClasses_List() {
        final List<String> list = new ArrayList();
        List<Class result = ClassUtils.convertClassNamesToClasses(list);
        assertEquals(0, result.size());

        list.add("java.lang.String");
        list.add("java.lang.xxx");
        list.add("java.lang.Object");
        result = ClassUtils.convertClassNamesToClasses(list);
        assertEquals(3, result.size());
        assertEquals(String.class, result.get(0));
        assertEquals(null, result.get(1));
        assertEquals(Object.class, result.get(2));

        @SuppressWarnings("unchecked") // test what happens when non-generic code adds wrong type of element
        final
        List<Object> olist = (List