Spring Framework example source code file (ComparatorTests.java)

This example Spring Framework source code file (ComparatorTests.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 - Spring Framework tags/keywords

boolean, comparable, comparablecomparator, comparator, comparator, comparatortests, compoundcomparator, dog, dog, object, propertycomparator, propertycomparator, string, string, util

The Spring Framework ComparatorTests.java source code

/*
 * Copyright 2002-2005 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 org.springframework.util.comparator;

import java.util.Comparator;

import junit.framework.TestCase;

import org.springframework.beans.support.PropertyComparator;

/**
 * @author Keith Donald
 */
public class ComparatorTests extends TestCase {

	public void testComparableComparator() {
		Comparator c = new ComparableComparator();
		String s1 = "abc";
		String s2 = "cde";
		assertTrue(c.compare(s1, s2) < 0);
	}

	public void testComparableComparatorIllegalArgs() {
		Comparator c = new ComparableComparator();
		Object o1 = new Object();
		Object o2 = new Object();
		try {
			c.compare(o1, o2);
		}
		catch (IllegalArgumentException e) {
			return;
		}
		fail("Comparator should have thrown a cce");
	}

	public void testBooleanComparatorTrueLow() {
		Comparator c = BooleanComparator.TRUE_LOW;
		assertTrue(c.compare(new Boolean(true), new Boolean(false)) < 0);
	}

	public void testBooleanComparatorTrueHigh() {
		Comparator c = BooleanComparator.TRUE_HIGH;
		assertTrue(c.compare(new Boolean(true), new Boolean(false)) > 0);
		assertTrue(c.compare(Boolean.TRUE, Boolean.TRUE) == 0);
	}

	public void testPropertyComparator() {
		Dog dog = new Dog();
		dog.setNickName("mace");

		Dog dog2 = new Dog();
		dog2.setNickName("biscy");

		PropertyComparator c = new PropertyComparator("nickName", false, true);
		assertTrue(c.compare(dog, dog2) > 0);
		assertTrue(c.compare(dog, dog) == 0);
		assertTrue(c.compare(dog2, dog) < 0);
	}

	public void testPropertyComparatorNulls() {
		Dog dog = new Dog();
		Dog dog2 = new Dog();
		PropertyComparator c = new PropertyComparator("nickName", false, true);
		assertTrue(c.compare(dog, dog2) == 0);
	}

	public void testNullSafeComparatorNullsLow() {
		Comparator c = NullSafeComparator.NULLS_LOW;
		assertTrue(c.compare(null, "boo") < 0);
	}

	public void testNullSafeComparatorNullsHigh() {
		Comparator c = NullSafeComparator.NULLS_HIGH;
		assertTrue(c.compare(null, "boo") > 0);
		assertTrue(c.compare(null, null) == 0);
	}

	public void testCompoundComparatorEmpty() {
		Comparator c = new CompoundComparator();
		try {
			c.compare("foo", "bar");
		}
		catch (IllegalStateException e) {
			return;
		}
		fail("illegal state should've been thrown on empty list");
	}

	public void testCompoundComparator() {
		CompoundComparator c = new CompoundComparator();
		c.addComparator(new PropertyComparator("lastName", false, true));

		Dog dog1 = new Dog();
		dog1.setFirstName("macy");
		dog1.setLastName("grayspots");

		Dog dog2 = new Dog();
		dog2.setFirstName("biscuit");
		dog2.setLastName("grayspots");

		assertTrue(c.compare(dog1, dog2) == 0);

		c.addComparator(new PropertyComparator("firstName", false, true));
		assertTrue(c.compare(dog1, dog2) > 0);

		dog2.setLastName("konikk dog");
		assertTrue(c.compare(dog2, dog1) > 0);
	}

	public void testCompoundComparatorInvert() {
		CompoundComparator c = new CompoundComparator();
		c.addComparator(new PropertyComparator("lastName", false, true));
		c.addComparator(new PropertyComparator("firstName", false, true));
		Dog dog1 = new Dog();
		dog1.setFirstName("macy");
		dog1.setLastName("grayspots");

		Dog dog2 = new Dog();
		dog2.setFirstName("biscuit");
		dog2.setLastName("grayspots");

		assertTrue(c.compare(dog1, dog2) > 0);
		c.invertOrder();
		assertTrue(c.compare(dog1, dog2) < 0);
	}


	private static class Dog implements Comparable {

		private String nickName;

		private String firstName;

		private String lastName;

		public int compareTo(Object o) {
			return nickName.compareTo(((Dog)o).nickName);
		}

		public String getNickName() {
			return nickName;
		}

		public void setNickName(String nickName) {
			this.nickName = nickName;
		}

		public String getFirstName() {
			return firstName;
		}

		public void setFirstName(String firstName) {
			this.firstName = firstName;
		}

		public String getLastName() {
			return lastName;
		}

		public void setLastName(String lastName) {
			this.lastName = lastName;
		}
	}

}