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	/*
	* 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.MBeanConstructorInfo;
	import javax.management.MBeanParameterInfo;


	/**
	* Describes a constructor of an Open MBean.
	*
	*
	* @since 1.5
	*/
	public class OpenMBeanConstructorInfoSupport
	extends MBeanConstructorInfo
	implements OpenMBeanConstructorInfo {

	/* Serial version */
	static final long serialVersionUID = -4400441579007477003L;


	// 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 OpenMBeanConstructorInfoSupport}
	* instance, which describes the constructor of a class of open
	* MBeans with the specified {@code name}, {@code description} and
	* {@code signature}.</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.
	*
	* @throws IllegalArgumentException if {@code name} or {@code
	* description} are null or empty string.
	*
	* @throws ArrayStoreException If {@code signature} is not an
	* array of instances of a subclass of {@code MBeanParameterInfo}.
	*/
	public OpenMBeanConstructorInfoSupport(String name,
	String description,
	OpenMBeanParameterInfo[] signature) {
	this(name, description, signature, (Descriptor) null);
	}

	/**
	* <p>Constructs an {@code OpenMBeanConstructorInfoSupport}
	* instance, which describes the constructor of a class of open
	* MBeans with the specified {@code name}, {@code description},
	* {@code signature}, 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 descriptor The descriptor for the constructor. This may
	* be null which is equivalent to an empty descriptor.
	*
	* @throws IllegalArgumentException if {@code name} or {@code
	* description} are null or empty string.
	*
	* @throws ArrayStoreException If {@code signature} is not an
	* array of instances of a subclass of {@code MBeanParameterInfo}.
	*
	* @since 1.6
	*/
	public OpenMBeanConstructorInfoSupport(String name,
	String description,
	OpenMBeanParameterInfo[] signature,
	Descriptor descriptor) {
	super(name,
	description,
	arrayCopyCast(signature), // may throw an ArrayStoreException
	descriptor);

	// 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");
	}

	}

	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;
	}


	/* * Commodity methods from java.lang.Object * */


	/**
	* <p>Compares the specified {@code obj} parameter with this
	* {@code OpenMBeanConstructorInfoSupport} 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
	* OpenMBeanConstructorInfo} interface,</li>
	* <li>their names are equal</li>
	* <li>their signatures are equal.</li>
	* </ul>
	*
	* This ensures that this {@code equals} method works properly for
	* {@code obj} parameters which are different implementations of
	* the {@code OpenMBeanConstructorInfo} interface.
	*
	* @param obj the object to be compared for equality with this
	* {@code OpenMBeanConstructorInfoSupport} instance;
	*
	* @return {@code true} if the specified object is equal to this
	* {@code OpenMBeanConstructorInfoSupport} instance.
	*/
	public boolean equals(Object obj) {

	// if obj is null, return false
	//
	if (obj == null) {
	return false;
	}

	// if obj is not a OpenMBeanConstructorInfo, return false
	//
	OpenMBeanConstructorInfo other;
	try {
	other = (OpenMBeanConstructorInfo) obj;
	} catch (ClassCastException e) {
	return false;
	}

	// Now, really test for equality between this
	// OpenMBeanConstructorInfo 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;
	}

	// All tests for equality were successfull
	//
	return true;
	}

	/**
	* <p>Returns the hash code value for this {@code
	* OpenMBeanConstructorInfoSupport} instance.</p>
	*
	* <p>The hash code of an {@code OpenMBeanConstructorInfoSupport}
	* instance is the sum of the hash codes of all elements of
	* information used in {@code equals} comparisons (ie: its name
	* 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
	* OpenMBeanConstructorInfoSupport} 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 OpenMBeanConstructorInfo} interface may be equal to
	* this {@code OpenMBeanConstructorInfoSupport} 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 OpenMBeanConstructorInfoSupport} 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
	* OpenMBeanConstructorInfoSupport} 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();
	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
	* OpenMBeanConstructorInfoSupport} instance.</p>
	*
	* <p>The string representation consists of the name of this class
	* (ie {@code
	* javax.management.openmbean.OpenMBeanConstructorInfoSupport}),
	* the name and signature of the described constructor and the
	* string representation of its descriptor.</p>
	*
	* <p>As {@code OpenMBeanConstructorInfoSupport} 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
	* OpenMBeanConstructorInfoSupport} instance
	*/
	public String toString() {

	// Calculate the string 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(",descriptor=")
	.append(this.getDescriptor())
	.append(")")
	.toString();
	}

	// return always the same string representation for this
	// instance (immutable)
	//
	return myToString;
	}

	}

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