1 /*
   2  * Copyright (c) 2000, 2007, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 
  27 package javax.management.openmbean;
  28 
  29 
  30 // java import
  31 //
  32 import java.util.Collection;
  33 
  34 // jmx import
  35 //
  36 
  37 
  38 /**
  39  * The <tt>CompositeData</tt> interface specifies the behavior of a specific type of complex <i>open data</i> objects
  40  * which represent <i>composite data</i> structures.
  41  *
  42  *
  43  * @since 1.5
  44  */
  45 public interface CompositeData {
  46 
  47 
  48     /**
  49      * Returns the <i>composite type </i> of this <i>composite data</i> instance.
  50      *
  51      * @return the type of this CompositeData.
  52      */
  53     public CompositeType getCompositeType();
  54 
  55     /**
  56      * Returns the value of the item whose name is <tt>key</tt>.
  57      *
  58      * @param key the name of the item.
  59      *
  60      * @return the value associated with this key.
  61      *
  62      * @throws IllegalArgumentException  if <tt>key</tt> is a null or empty String.
  63      *
  64      * @throws InvalidKeyException  if <tt>key</tt> is not an existing item name for this <tt>CompositeData</tt> instance.
  65      */
  66     public Object get(String key) ;
  67 
  68     /**
  69      * Returns an array of the values of the items whose names are specified by <tt>keys</tt>, in the same order as <tt>keys</tt>.
  70      *
  71      * @param keys the names of the items.
  72      *
  73      * @return the values corresponding to the keys.
  74      *
  75      * @throws IllegalArgumentException  if an element in <tt>keys</tt> is a null or empty String.
  76      *
  77      * @throws InvalidKeyException  if an element in <tt>keys</tt> is not an existing item name for this <tt>CompositeData</tt> instance.
  78      */
  79     public Object[] getAll(String[] keys) ;
  80 
  81     /**
  82      * Returns <tt>true</tt> if and only if this <tt>CompositeData</tt> instance contains
  83      * an item whose name is <tt>key</tt>.
  84      * If <tt>key</tt> is a null or empty String, this method simply returns false.
  85      *
  86      * @param key the key to be tested.
  87      *
  88      * @return true if this <tt>CompositeData</tt> contains the key.
  89      */
  90     public boolean containsKey(String key) ;
  91 
  92     /**
  93      * Returns <tt>true</tt> if and only if this <tt>CompositeData</tt> instance contains an item
  94      * whose value is <tt>value</tt>.
  95      *
  96      * @param value the value to be tested.
  97      *
  98      * @return true if this <tt>CompositeData</tt> contains the value.
  99      */
 100     public boolean containsValue(Object value) ;
 101 
 102     /**
 103      * Returns an unmodifiable Collection view of the item values contained in this <tt>CompositeData</tt> instance.
 104      * The returned collection's iterator will return the values in the ascending lexicographic order of the corresponding
 105      * item names.
 106      *
 107      * @return the values.
 108      */
 109     public Collection<?> values() ;
 110 
 111     /**
 112      * Compares the specified <var>obj</var> parameter with this
 113      * <code>CompositeData</code> instance for equality.
 114      * <p>
 115      * Returns <tt>true</tt> if and only if all of the following statements are true:
 116      * <ul>
 117      * <li><var>obj</var> is non null,</li>
 118      * <li><var>obj</var> also implements the <code>CompositeData</code> interface,</li>
 119      * <li>their composite types are equal</li>
 120      * <li>their contents, i.e. (name, value) pairs are equal. If a value contained in
 121      * the content is an array, the value comparison is done as if by calling
 122      * the {@link java.util.Arrays#deepEquals(Object[], Object[]) deepEquals} method
 123      * for arrays of object reference types or the appropriate overloading of
 124      * {@code Arrays.equals(e1,e2)} for arrays of primitive types</li>
 125      * </ul>
 126      * <p>
 127      * This ensures that this <tt>equals</tt> method works properly for
 128      * <var>obj</var> parameters which are different implementations of the
 129      * <code>CompositeData</code> interface, with the restrictions mentioned in the
 130      * {@link java.util.Collection#equals(Object) equals}
 131      * method of the <tt>java.util.Collection</tt> interface.
 132      *
 133      * @param  obj  the object to be compared for equality with this
 134      * <code>CompositeData</code> instance.
 135      * @return  <code>true</code> if the specified object is equal to this
 136      * <code>CompositeData</code> instance.
 137      */
 138     public boolean equals(Object obj) ;
 139 
 140     /**
 141      * Returns the hash code value for this <code>CompositeData</code> instance.
 142      * <p>
 143      * The hash code of a <code>CompositeData</code> instance is the sum of the hash codes
 144      * of all elements of information used in <code>equals</code> comparisons
 145      * (ie: its <i>composite type</i> and all the item values).
 146      * <p>
 147      * This ensures that <code> t1.equals(t2) </code> implies that <code> t1.hashCode()==t2.hashCode() </code>
 148      * for any two <code>CompositeData</code> instances <code>t1</code> and <code>t2</code>,
 149      * as required by the general contract of the method
 150      * {@link Object#hashCode() Object.hashCode()}.
 151      * <p>
 152      * Each item value's hash code is added to the returned hash code.
 153      * If an item value is an array,
 154      * its hash code is obtained as if by calling the
 155      * {@link java.util.Arrays#deepHashCode(Object[]) deepHashCode} method
 156      * for arrays of object reference types or the appropriate overloading
 157      * of {@code Arrays.hashCode(e)} for arrays of primitive types.
 158      *
 159      * @return the hash code value for this <code>CompositeData</code> instance
 160      */
 161     public int hashCode() ;
 162 
 163     /**
 164      * Returns a string representation of this <code>CompositeData</code> instance.
 165      * <p>
 166      * The string representation consists of the name of the implementing class,
 167      * the string representation of the composite type of this instance, and the string representation of the contents
 168      * (ie list the itemName=itemValue mappings).
 169      *
 170      * @return  a string representation of this <code>CompositeData</code> instance
 171      */
 172     public String toString() ;
 173 
 174 }