/* * Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */  package javax.management.openmbean;  // java import//import java.util.Arrays; import javax.management.Descriptor;import javax.management.ImmutableDescriptor;import javax.management.MBeanOperationInfo;import javax.management.MBeanParameterInfo;  /** * Describes an operation of an Open MBean. * * * @since 1.5 */public class OpenMBeanOperationInfoSupport    extends MBeanOperationInfo    implements OpenMBeanOperationInfo {     /* Serial version */    static final long serialVersionUID = 4996859732565369366L;     /**     * @serial The <i>open type</i> of the values returned by the operation     *         described by this {@link OpenMBeanOperationInfo} instance     *     */    private OpenType<?> returnOpenType;      // As this instance is immutable,    // these two values need only be calculated once.    private transient Integer myHashCode = null;    private transient String  myToString = null;      /**     * <p>Constructs an {@code OpenMBeanOperationInfoSupport}     * instance, which describes the operation of a class of open     * MBeans, with the specified {@code name}, {@code description},     * {@code signature}, {@code returnOpenType} and {@code     * impact}.</p>     *     * <p>The {@code signature} array parameter is internally copied,     * so that subsequent changes to the array referenced by {@code     * signature} have no effect on this instance.</p>     *     * @param name cannot be a null or empty string.     *     * @param description cannot be a null or empty string.     *     * @param signature can be null or empty if there are no     * parameters to describe.     *     * @param returnOpenType cannot be null: use {@code     * SimpleType.VOID} for operations that return nothing.     *     * @param impact must be one of {@code ACTION}, {@code     * ACTION_INFO}, {@code INFO}, or {@code UNKNOWN}.     *     * @throws IllegalArgumentException if {@code name} or {@code     * description} are null or empty string, or {@code     * returnOpenType} is null, or {@code impact} is not one of {@code     * ACTION}, {@code ACTION_INFO}, {@code INFO}, or {@code UNKNOWN}.     *     * @throws ArrayStoreException If {@code signature} is not an     * array of instances of a subclass of {@code MBeanParameterInfo}.     */    public OpenMBeanOperationInfoSupport(String name,                                         String description,                                         OpenMBeanParameterInfo[] signature,                                         OpenType<?> returnOpenType,                                         int impact) {        this(name, description, signature, returnOpenType, impact,             (Descriptor) null);    }     /**     * <p>Constructs an {@code OpenMBeanOperationInfoSupport}     * instance, which describes the operation of a class of open     * MBeans, with the specified {@code name}, {@code description},     * {@code signature}, {@code returnOpenType}, {@code     * impact}, and {@code descriptor}.</p>     *     * <p>The {@code signature} array parameter is internally copied,     * so that subsequent changes to the array referenced by {@code     * signature} have no effect on this instance.</p>     *     * @param name cannot be a null or empty string.     *     * @param description cannot be a null or empty string.     *     * @param signature can be null or empty if there are no     * parameters to describe.     *     * @param returnOpenType cannot be null: use {@code     * SimpleType.VOID} for operations that return nothing.     *     * @param impact must be one of {@code ACTION}, {@code     * ACTION_INFO}, {@code INFO}, or {@code UNKNOWN}.     *     * @param descriptor The descriptor for the operation.  This may     * be null, which is equivalent to an empty descriptor.     *     * @throws IllegalArgumentException if {@code name} or {@code     * description} are null or empty string, or {@code     * returnOpenType} is null, or {@code impact} is not one of {@code     * ACTION}, {@code ACTION_INFO}, {@code INFO}, or {@code UNKNOWN}.     *     * @throws ArrayStoreException If {@code signature} is not an     * array of instances of a subclass of {@code MBeanParameterInfo}.     *     * @since 1.6     */    public OpenMBeanOperationInfoSupport(String name,                                         String description,                                         OpenMBeanParameterInfo[] signature,                                         OpenType<?> returnOpenType,                                         int impact,                                         Descriptor descriptor) {        super(name,              description,              arrayCopyCast(signature),              // must prevent NPE here - we will throw IAE later on if              // returnOpenType is null              (returnOpenType == null) ? null : returnOpenType.getClassName(),              impact,              ImmutableDescriptor.union(descriptor,                // must prevent NPE here - we will throw IAE later on if                // returnOpenType is null                (returnOpenType==null) ? null :returnOpenType.getDescriptor()));         // check parameters that should not be null or empty        // (unfortunately it is not done in superclass :-( ! )        //        if (name == null || name.trim().equals("")) {            throw new IllegalArgumentException("Argument name cannot " +                                               "be null or empty");        }        if (description == null || description.trim().equals("")) {            throw new IllegalArgumentException("Argument description cannot " +                                               "be null or empty");        }        if (returnOpenType == null) {            throw new IllegalArgumentException("Argument returnOpenType " +                                               "cannot be null");        }         if (impact != ACTION && impact != ACTION_INFO && impact != INFO &&                impact != UNKNOWN) {            throw new IllegalArgumentException("Argument impact can only be " +                                               "one of ACTION, ACTION_INFO, " +                                               "INFO, or UNKNOWN: " + impact);        }         this.returnOpenType = returnOpenType;    }      // Converts an array of OpenMBeanParameterInfo objects extending    // MBeanParameterInfo into an array of MBeanParameterInfo.    //    private static MBeanParameterInfo[]            arrayCopyCast(OpenMBeanParameterInfo[] src) {        if (src == null)            return null;         MBeanParameterInfo[] dst = new MBeanParameterInfo[src.length];        System.arraycopy(src, 0, dst, 0, src.length);        // may throw an ArrayStoreException        return dst;    }     // Converts an array of MBeanParameterInfo objects implementing    // OpenMBeanParameterInfo into an array of OpenMBeanParameterInfo.    //    private static OpenMBeanParameterInfo[]            arrayCopyCast(MBeanParameterInfo[] src) {        if (src == null)            return null;         OpenMBeanParameterInfo[] dst = new OpenMBeanParameterInfo[src.length];        System.arraycopy(src, 0, dst, 0, src.length);        // may throw an ArrayStoreException        return dst;    }      // [JF]: should we add constructor with java.lang.reflect.Method    // method parameter ?  would need to add consistency check between    // OpenType<?> returnOpenType and method.getReturnType().      /**     * Returns the <i>open type</i> of the values returned by the     * operation described by this {@code OpenMBeanOperationInfo}     * instance.     */    public OpenType<?> getReturnOpenType() {         return returnOpenType;    }       /* ***  Commodity methods from java.lang.Object  *** */      /**     * <p>Compares the specified {@code obj} parameter with this     * {@code OpenMBeanOperationInfoSupport} instance for     * equality.</p>     *     * <p>Returns {@code true} if and only if all of the following     * statements are true:     *     * <ul>     * <li>{@code obj} is non null,</li>     * <li>{@code obj} also implements the {@code     * OpenMBeanOperationInfo} interface,</li>     * <li>their names are equal</li>     * <li>their signatures are equal</li>     * <li>their return open types are equal</li>     * <li>their impacts are equal</li>     * </ul>     *     * This ensures that this {@code equals} method works properly for     * {@code obj} parameters which are different implementations of     * the {@code OpenMBeanOperationInfo} interface.     *     * @param obj the object to be compared for equality with this     * {@code OpenMBeanOperationInfoSupport} instance;     *     * @return {@code true} if the specified object is equal to this     * {@code OpenMBeanOperationInfoSupport} instance.     */    public boolean equals(Object obj) {         // if obj is null, return false        //        if (obj == null) {            return false;        }         // if obj is not a OpenMBeanOperationInfo, return false        //        OpenMBeanOperationInfo other;        try {            other = (OpenMBeanOperationInfo) obj;        } catch (ClassCastException e) {            return false;        }         // Now, really test for equality between this        // OpenMBeanOperationInfo implementation and the other:        //         // their Name should be equal        if ( ! this.getName().equals(other.getName()) ) {            return false;        }         // their Signatures should be equal        if ( ! Arrays.equals(this.getSignature(), other.getSignature()) ) {            return false;        }         // their return open types should be equal        if ( ! this.getReturnOpenType().equals(other.getReturnOpenType()) ) {            return false;        }         // their impacts should be equal        if ( this.getImpact() != other.getImpact() ) {            return false;        }         // All tests for equality were successfull        //        return true;    }     /**     * <p>Returns the hash code value for this {@code     * OpenMBeanOperationInfoSupport} instance.</p>     *     * <p>The hash code of an {@code OpenMBeanOperationInfoSupport}     * instance is the sum of the hash codes of all elements of     * information used in {@code equals} comparisons (ie: its name,     * return open type, impact and signature, where the signature     * hashCode is calculated by a call to {@code     * java.util.Arrays.asList(this.getSignature).hashCode()}).</p>     *     * <p>This ensures that {@code t1.equals(t2) } implies that {@code     * t1.hashCode()==t2.hashCode() } for any two {@code     * OpenMBeanOperationInfoSupport} instances {@code t1} and {@code     * t2}, as required by the general contract of the method {@link     * Object#hashCode() Object.hashCode()}.</p>     *     * <p>However, note that another instance of a class implementing     * the {@code OpenMBeanOperationInfo} interface may be equal to     * this {@code OpenMBeanOperationInfoSupport} instance as defined     * by {@link #equals(java.lang.Object)}, but may have a different     * hash code if it is calculated differently.</p>     *     * <p>As {@code OpenMBeanOperationInfoSupport} instances are     * immutable, the hash code for this instance is calculated once,     * on the first call to {@code hashCode}, and then the same value     * is returned for subsequent calls.</p>     *     * @return the hash code value for this {@code     * OpenMBeanOperationInfoSupport} instance     */    public int hashCode() {         // Calculate the hash code value if it has not yet been done        // (ie 1st call to hashCode())        //        if (myHashCode == null) {            int value = 0;            value += this.getName().hashCode();            value += Arrays.asList(this.getSignature()).hashCode();            value += this.getReturnOpenType().hashCode();            value += this.getImpact();            myHashCode = Integer.valueOf(value);        }         // return always the same hash code for this instance (immutable)        //        return myHashCode.intValue();    }     /**     * <p>Returns a string representation of this {@code     * OpenMBeanOperationInfoSupport} instance.</p>     *     * <p>The string representation consists of the name of this class     * (ie {@code     * javax.management.openmbean.OpenMBeanOperationInfoSupport}), and     * the name, signature, return open type and impact of the     * described operation and the string representation of its descriptor.</p>     *     * <p>As {@code OpenMBeanOperationInfoSupport} instances are     * immutable, the string representation for this instance is     * calculated once, on the first call to {@code toString}, and     * then the same value is returned for subsequent calls.</p>     *     * @return a string representation of this {@code     * OpenMBeanOperationInfoSupport} instance     */    public String toString() {         // Calculate the hash code value if it has not yet been done        // (ie 1st call to toString())        //        if (myToString == null) {            myToString = new StringBuilder()                .append(this.getClass().getName())                .append("(name=")                .append(this.getName())                .append(",signature=")                .append(Arrays.asList(this.getSignature()).toString())                .append(",return=")                .append(this.getReturnOpenType().toString())                .append(",impact=")                .append(this.getImpact())                .append(",descriptor=")                .append(this.getDescriptor())                .append(")")                .toString();        }         // return always the same string representation for this        // instance (immutable)        //        return myToString;    }     /**     * An object serialized in a version of the API before Descriptors were     * added to this class will have an empty or null Descriptor.     * For consistency with our     * behavior in this version, we must replace the object with one     * where the Descriptors reflect the same value of returned openType.     **/    private Object readResolve() {        if (getDescriptor().getFieldNames().length == 0) {            // This constructor will construct the expected default Descriptor.            //            return new OpenMBeanOperationInfoSupport(                    name, description, arrayCopyCast(getSignature()),                    returnOpenType, getImpact());        } else            return this;    } }