1 /*
   2  * Copyright (c) 1997, 2012, 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
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   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 package javax.activation;
  27 
  28 import java.awt.datatransfer.DataFlavor;
  29 import java.io.IOException;
  30 import javax.activation.MimeType;
  31 
  32 /**
  33  * The ActivationDataFlavor class is a special subclass of
  34  * {@code java.awt.datatransfer.DataFlavor}. It allows the JAF to
  35  * set all three values stored by the DataFlavor class via a new
  36  * constructor. It also contains improved MIME parsing in the {@code equals}
  37  * method. Except for the improved parsing, its semantics are
  38  * identical to that of the JDK's DataFlavor class.
  39  *
  40  * @since 1.6
  41  */
  42 
  43 public class ActivationDataFlavor extends DataFlavor {
  44 
  45     /*
  46      * Raison d'etre:
  47      *
  48      * The DataFlavor class included in JDK 1.1 has several limitations
  49      * including piss poor MIME type parsing, and the limitation of
  50      * only supporting serialized objects and InputStreams as
  51      * representation objects. This class 'fixes' that.
  52      */
  53 
  54     // I think for now I'll keep copies of all the variables and
  55     // then later I may choose try to better coexist with the base
  56     // class *sigh*
  57     private String mimeType = null;
  58     private MimeType mimeObject = null;
  59     private String humanPresentableName = null;
  60     private Class representationClass = null;
  61 
  62     /**
  63      * Construct a DataFlavor that represents an arbitrary
  64      * Java object. This constructor is an extension of the
  65      * JDK's DataFlavor in that it allows the explicit setting
  66      * of all three DataFlavor attributes.
  67      * <p>
  68      * The returned DataFlavor will have the following characteristics:
  69      * <p>
  70      * representationClass = representationClass<br>
  71      * mimeType            = mimeType<br>
  72      * humanName           = humanName
  73      *
  74      * @param representationClass the class used in this DataFlavor
  75      * @param mimeType the MIME type of the data represented by this class
  76      * @param humanPresentableName the human presentable name of the flavor
  77      */
  78     public ActivationDataFlavor(Class representationClass,
  79                       String mimeType, String humanPresentableName) {
  80         super(mimeType, humanPresentableName); // need to call super
  81 
  82         // init private variables:
  83         this.mimeType = mimeType;
  84         this.humanPresentableName = humanPresentableName;
  85         this.representationClass = representationClass;
  86     }
  87 
  88     /**
  89      * Construct a DataFlavor that represents a MimeType.
  90      * <p>
  91      * The returned DataFlavor will have the following characteristics:
  92      * <p>
  93      * If the mimeType is "application/x-java-serialized-object;
  94      * class=", the result is the same as calling new
  95      * DataFlavor(Class.forName()) as above.
  96      * <p>
  97      * otherwise:
  98      * <p>
  99      * representationClass = InputStream<p>
 100      * mimeType = mimeType
 101      *
 102      * @param representationClass the class used in this DataFlavor
 103      * @param humanPresentableName the human presentable name of the flavor
 104      */
 105     public ActivationDataFlavor(Class representationClass,
 106                                 String humanPresentableName) {
 107         super(representationClass, humanPresentableName);
 108         this.mimeType = super.getMimeType();
 109         this.representationClass = representationClass;
 110         this.humanPresentableName = humanPresentableName;
 111     }
 112 
 113     /**
 114      * Construct a DataFlavor that represents a MimeType.
 115      * <p>
 116      * The returned DataFlavor will have the following characteristics:
 117      * <p>
 118      * If the mimeType is "application/x-java-serialized-object; class=",
 119      * the result is the same as calling new DataFlavor(Class.forName()) as
 120      * above, otherwise:
 121      * <p>
 122      * representationClass = InputStream<p>
 123      * mimeType = mimeType
 124      *
 125      * @param mimeType the MIME type of the data represented by this class
 126      * @param humanPresentableName the human presentable name of the flavor
 127      */
 128     public ActivationDataFlavor(String mimeType, String humanPresentableName) {
 129         super(mimeType, humanPresentableName);
 130         this.mimeType = mimeType;
 131         try {
 132             this.representationClass = Class.forName("java.io.InputStream");
 133         } catch (ClassNotFoundException ex) {
 134             // XXX - should never happen, ignore it
 135         }
 136         this.humanPresentableName = humanPresentableName;
 137     }
 138 
 139     /**
 140      * Return the MIME type for this DataFlavor.
 141      *
 142      * @return  the MIME type
 143      */
 144     public String getMimeType() {
 145         return mimeType;
 146     }
 147 
 148     /**
 149      * Return the representation class.
 150      *
 151      * @return  the representation class
 152      */
 153     public Class getRepresentationClass() {
 154         return representationClass;
 155     }
 156 
 157     /**
 158      * Return the Human Presentable name.
 159      *
 160      * @return  the human presentable name
 161      */
 162     public String getHumanPresentableName() {
 163         return humanPresentableName;
 164     }
 165 
 166     /**
 167      * Set the human presentable name.
 168      *
 169      * @param humanPresentableName      the name to set
 170      */
 171     public void setHumanPresentableName(String humanPresentableName) {
 172         this.humanPresentableName = humanPresentableName;
 173     }
 174 
 175     /**
 176      * Compares the DataFlavor passed in with this DataFlavor; calls
 177      * the {@code isMimeTypeEqual} method.
 178      *
 179      * @param dataFlavor        the DataFlavor to compare with
 180      * @return                  true if the MIME type and representation class
 181      *                          are the same
 182      */
 183     public boolean equals(DataFlavor dataFlavor) {
 184         return (isMimeTypeEqual(dataFlavor) &&
 185                 dataFlavor.getRepresentationClass() == representationClass);
 186     }
 187 
 188     /**
 189      * Is the string representation of the MIME type passed in equivalent
 190      * to the MIME type of this DataFlavor. <p>
 191      *
 192      * ActivationDataFlavor delegates the comparison of MIME types to
 193      * the MimeType class included as part of the JavaBeans Activation
 194      * Framework. This provides a more robust comparison than is normally
 195      * available in the DataFlavor class.
 196      *
 197      * @param mimeType  the MIME type
 198      * @return          true if the same MIME type
 199      */
 200     public boolean isMimeTypeEqual(String mimeType) {
 201         MimeType mt = null;
 202         try {
 203             if (mimeObject == null)
 204                 mimeObject = new MimeType(this.mimeType);
 205             mt = new MimeType(mimeType);
 206         } catch (MimeTypeParseException e) {
 207             // something didn't parse, do a crude comparison
 208             return this.mimeType.equalsIgnoreCase(mimeType);
 209         }
 210 
 211         return mimeObject.match(mt);
 212     }
 213 
 214     /**
 215      * Called on DataFlavor for every MIME Type parameter to allow DataFlavor
 216      * subclasses to handle special parameters like the text/plain charset
 217      * parameters, whose values are case insensitive.  (MIME type parameter
 218      * values are supposed to be case sensitive).
 219      * <p>
 220      * This method is called for each parameter name/value pair and should
 221      * return the normalized representation of the parameterValue.
 222      * This method is never invoked by this implementation.
 223      *
 224      * @param parameterName     the parameter name
 225      * @param parameterValue    the parameter value
 226      * @return                  the normalized parameter value
 227      * @deprecated
 228      */
 229     protected String normalizeMimeTypeParameter(String parameterName,
 230                                                 String parameterValue) {
 231         return parameterValue;
 232     }
 233 
 234     /**
 235      * Called for each MIME type string to give DataFlavor subtypes the
 236      * opportunity to change how the normalization of MIME types is
 237      * accomplished.
 238      * One possible use would be to add default parameter/value pairs in cases
 239      * where none are present in the MIME type string passed in.
 240      * This method is never invoked by this implementation.
 241      *
 242      * @param mimeType  the MIME type
 243      * @return          the normalized MIME type
 244      * @deprecated
 245      */
 246     protected String normalizeMimeType(String mimeType) {
 247         return mimeType;
 248     }
 249 }