ObjectUtils.java Source code

Introduction

Here is the source code for ObjectUtils.java

Source

import java.lang.reflect.Array;
import java.util.Arrays;

/*
 * Copyright 2002-2007 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.
 */

//Revised from springframework

/**
 * Miscellaneous object utility methods. Mainly for internal use within the
 * framework; consider Jakarta's Commons Lang for a more comprehensive suite
 * of object utilities.
 *
 * @author Juergen Hoeller
 * @author Keith Donald
 * @author Rod Johnson
 * @author Rob Harrop
 * @author Alex Ruiz
 * @since 19.03.2004
 * @see org.apache.commons.lang.ObjectUtils
 */
abstract class ObjectUtils {

    private static final int INITIAL_HASH = 7;
    private static final int MULTIPLIER = 31;

    private static final String EMPTY_STRING = "";
    private static final String NULL_STRING = "null";
    private static final String ARRAY_START = "{";
    private static final String ARRAY_END = "}";
    private static final String EMPTY_ARRAY = ARRAY_START + ARRAY_END;
    private static final String ARRAY_ELEMENT_SEPARATOR = ", ";

    /**
     * Return a String representation of an object's overall identity.
     * @param obj the object (may be <code>null</code>)
     * @return the object's identity as String representation,
     * or an empty String if the object was <code>null</code>
     */
    public static String identityToString(Object obj) {
        if (obj == null) {
            return EMPTY_STRING;
        }
        return obj.getClass().getName() + "@" + getIdentityHexString(obj);
    }

    /**
     * Return a hex String form of an object's identity hash code.
     * @param obj the object
     * @return the object's identity code in hex notation
     */
    public static String getIdentityHexString(Object obj) {
        return Integer.toHexString(System.identityHashCode(obj));
    }

}