org.marketcetera.util.test.EqualityAssert.java Source code

Introduction

Here is the source code for org.marketcetera.util.test.EqualityAssert.java

Source

package org.marketcetera.util.test;

import org.apache.commons.lang.math.NumberUtils;

import static org.junit.Assert.*;

/**
 * Assertions for equality (and hash code generation).
 * 
 * @author tlerios@marketcetera.com
 * @since 1.0.0
 * @version $Id$
 */

/* $License$ */

public final class EqualityAssert {

    // CLASS METHODS.

    /**
     * Asserts that the given target object implements equality
     * correctly. If the assertion does not hold, the {@link
     * AssertionError} thrown starts with the given message, which may
     * be null if no such custom message prefix is desired.
     *
     * @param message The message.
     * @param o The target object.
     * @param oEqual Another object that is equal to (but not the same
     * as) the target object.
     * @param osUnequal Objects that are all unequal to the target
     * object. It may be null or contain null elements.
     */

    public static void assertEquality(String message, Object o, Object oEqual, Object... osUnequal) {
        String content = null;
        if (!o.equals(o)) {
            content = "'" + o + "' unequal to self"; //$NON-NLS-1$ //$NON-NLS-2$
        } else if (!o.equals(oEqual)) {
            content = "'" + o + "' unequal to '" + //$NON-NLS-1$ //$NON-NLS-2$
                    oEqual + "'"; //$NON-NLS-1$
        } else if (!oEqual.equals(o)) {
            content = "'" + oEqual + "' unequal to '" + //$NON-NLS-1$ //$NON-NLS-2$
                    o + "'"; //$NON-NLS-1$
        } else if (oEqual == o) {
            content = "'" + oEqual + "' same as '" + //$NON-NLS-1$ //$NON-NLS-2$
                    o + "'"; //$NON-NLS-1$
        } else if (osUnequal != null) {
            for (Object oUnequal : osUnequal) {
                if (o.equals(oUnequal)) {
                    content = "'" + o + "' equal to '" + //$NON-NLS-1$ //$NON-NLS-2$
                            oUnequal + "'"; //$NON-NLS-1$ 
                    break;
                }
                if ((oUnequal != null) && (oUnequal.equals(o))) {
                    content = "'" + oUnequal + //$NON-NLS-1$ 
                            "' equal to '" + o + "'"; //$NON-NLS-1$ //$NON-NLS-2$
                    break;
                }
            }
        }
        if (content == null) {
            if (o.equals(null)) {
                content = "'" + o + "' equal to null"; //$NON-NLS-1$ //$NON-NLS-2$
            } else if (o.equals(NumberUtils.INTEGER_ZERO)) {
                content = "'" + o + "' equal to zero"; //$NON-NLS-1$ //$NON-NLS-2$
            } else if (o.hashCode() != oEqual.hashCode()) {
                content = "'" + o + //$NON-NLS-1$
                        "' hash code unequal to copy's '" + //$NON-NLS-1$
                        oEqual + "'"; //$NON-NLS-1$
            }
        }
        if (content == null) {
            return;
        }
        if (message != null) {
            content = message + " " + content; //$NON-NLS-1$
        }
        fail(content);
    }

    /**
     * Asserts that the given target object implements equality
     * correctly.
     *
     * @param o The target object.
     * @param oEqual Another object that is equal to (but not the same
     * as) the target object.
     * @param osUnequal Objects that are all unequal to the target
     * object. It may be null or contain null elements.
     */

    public static void assertEquality(Object o, Object oEqual, Object... osUnequal) {
        assertEquality(null, o, oEqual, osUnequal);
    }

    /**
     * Asserts that the given target object implements equality
     * correctly. If the assertion does not hold, the {@link
     * AssertionError} thrown starts with the given message, which may
     * be null if no such custom message prefix is desired.
     *
     * @param message The message.
     * @param o The target object.
     * @param equalIndex The index in the collection below for another
     * object that is equal to (but not the same as) the target
     * object; all other collection items are unequal to the target
     * object.
     * @param osOther A nonempty collection of objects.
     */

    public static void assertEquality(String message, Object o, int equalIndex, Object... osOther) {
        Object oEqual = null;
        Object[] osUnequal = new Object[osOther.length - 1];
        int j = 0;
        for (int i = 0; i < osOther.length; i++) {
            if (i == equalIndex) {
                oEqual = osOther[i];
            } else {
                osUnequal[j++] = osOther[i];
            }
        }
        assertEquality(message, o, oEqual, osUnequal);
    }

    /**
     * Asserts that the given target object implements equality
     * correctly.
     *
     * @param o The target object.
     * @param equalIndex The index in the collection below for another
     * object that is equal to (but not the same as) the target
     * object; all other collection items are unequal to the target
     * object.
     * @param osOther A nonempty collection of objects.
     */

    public static void assertEquality(Object o, int equalIndex, Object... osOther) {
        assertEquality(null, o, equalIndex, osOther);
    }

    // CONSTRUCTOR.

    /**
     * Constructor. It is private so that no instances can be created.
     */

    private EqualityAssert() {
    }
}