001 /* OpenMBeanConstructorInfoSupport.java -- Open typed info about an constructor.
002 Copyright (C) 2006 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038 package javax.management.openmbean;
039
040 import java.util.Arrays;
041
042 import javax.management.MBeanConstructorInfo;
043 import javax.management.MBeanParameterInfo;
044
045 /**
046 * Describes a constructor for an open management bean.
047 *
048 * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
049 * @since 1.5
050 */
051 public class OpenMBeanConstructorInfoSupport
052 extends MBeanConstructorInfo
053 implements OpenMBeanConstructorInfo
054 {
055
056 /**
057 * Compatible with JDK 1.5
058 */
059 private static final long serialVersionUID = -4400441579007477003L;
060
061 /**
062 * The hash code of this instance.
063 */
064 private transient Integer hashCode;
065
066 /**
067 * The <code>toString()</code> result of this instance.
068 */
069 private transient String string;
070
071 /**
072 * Constructs a @link{OpenMBeanConstructorInfo} with the specified
073 * name, description and parameter information. A <code>null</code>
074 * value for the parameter information is the same as passing in
075 * an empty array. Neither the name nor the description may be
076 * null or equal to the empty string. A copy of the parameter array
077 * is taken, so later changes have no effect.
078 *
079 * @param name the name of the constructor.
080 * @param desc a description of the constructor.
081 * @param sig the signature of the constructor, as a series
082 * of {@link MBeanParameterInfo} objects, one for
083 * each parameter.
084 * @throws IllegalArgumentException if the name or description is
085 * either <code>null</code>
086 * or the empty string.
087 * @throws ArrayStoreException if the members of the signature array
088 * are not assignable to
089 * {@link javax.management.MBeanParameterInfo}
090 */
091 public OpenMBeanConstructorInfoSupport(String name, String desc,
092 OpenMBeanParameterInfo[] sig)
093 {
094 super(name, desc, (MBeanParameterInfo[]) sig);
095 if (name == null)
096 throw new IllegalArgumentException("The name may not be null.");
097 if (desc == null)
098 throw new IllegalArgumentException("The description may not be null.");
099 if (name.length() == 0)
100 throw new IllegalArgumentException("The name may not be the empty string.");
101 if (desc.length() == 0)
102 throw new IllegalArgumentException("The description may not be the " +
103 "empty string.");
104 }
105
106 /**
107 * Compares this attribute with the supplied object. This returns
108 * true iff the object is an instance of {@link OpenMBeanConstructorInfo}
109 * with an equal name and signature.
110 *
111 * @param obj the object to compare.
112 * @return true if the object is a {@link OpenMBeanParameterInfo}
113 * instance,
114 * <code>name.equals(object.getName())</code>,
115 * and <code>signature.equals(object.getSignature())</code>.
116 */
117 public boolean equals(Object obj)
118 {
119 if (!(obj instanceof OpenMBeanConstructorInfo))
120 return false;
121 OpenMBeanConstructorInfo o = (OpenMBeanConstructorInfo) obj;
122 return getName().equals(o.getName()) &&
123 getSignature().equals(o.getSignature());
124 }
125
126 /**
127 * <p>
128 * Returns the hashcode of the constructor information as the sum of
129 * the hashcodes of the name and signature (calculated by
130 * <code>java.util.Arrays.asList(signature).hashCode()</code>).
131 * </p>
132 * <p>
133 * As instances of this class are immutable, the return value
134 * is computed just once for each instance and reused
135 * throughout its life.
136 * </p>
137 *
138 * @return the hashcode of the constructor information.
139 */
140 public int hashCode()
141 {
142 if (hashCode == null)
143 hashCode = Integer.valueOf(getName().hashCode() +
144 Arrays.asList(getSignature()).hashCode());
145 return hashCode.intValue();
146 }
147
148 /**
149 * <p>
150 * Returns a textual representation of this instance. This
151 * is constructed using the class name
152 * (<code>javax.management.openmbean.OpenMBeanConstructorInfo</code>)
153 * along with the name and signature.
154 * </p>
155 * <p>
156 * As instances of this class are immutable, the return value
157 * is computed just once for each instance and reused
158 * throughout its life.
159 * </p>
160 *
161 * @return a @link{java.lang.String} instance representing
162 * the instance in textual form.
163 */
164 public String toString()
165 {
166 if (string == null)
167 string = getClass().getName()
168 + "[name=" + getName()
169 + ",signature=" + Arrays.toString(getSignature())
170 + "]";
171 return string;
172 }
173
174 }