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Diffstat (limited to 'libjava/classpath/javax/swing/text/SimpleAttributeSet.java')
| -rw-r--r-- | libjava/classpath/javax/swing/text/SimpleAttributeSet.java | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/libjava/classpath/javax/swing/text/SimpleAttributeSet.java b/libjava/classpath/javax/swing/text/SimpleAttributeSet.java new file mode 100644 index 000000000..02299019b --- /dev/null +++ b/libjava/classpath/javax/swing/text/SimpleAttributeSet.java @@ -0,0 +1,415 @@ +/* SimpleAttributeSet.java -- + Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath 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 for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package javax.swing.text; + +import java.io.Serializable; +import java.util.Enumeration; +import java.util.Hashtable; + +/** + * A set of attributes. + */ +public class SimpleAttributeSet + implements MutableAttributeSet, Serializable, Cloneable +{ + /** The serialization UID (compatible with JDK1.5). */ + private static final long serialVersionUID = 8267656273837665219L; + + /** + * An empty attribute set. + */ + public static final AttributeSet EMPTY = new EmptyAttributeSet(); + + /** Storage for the attributes. */ + Hashtable tab; + + /** + * Creates a new attribute set that is initially empty. + */ + public SimpleAttributeSet() + { + tab = new Hashtable(); + } + + /** + * Creates a new <code>SimpleAttributeSet</code> with the same attributes + * and resolve parent as the specified set. + * + * @param a the attributes (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>a</code> is <code>null</code>. + */ + public SimpleAttributeSet(AttributeSet a) + { + tab = new Hashtable(); + addAttributes(a); + } + + /** + * Adds an attribute with the given <code>name</code> and <code>value</code> + * to the set. If the set already contains an attribute with the given + * <code>name</code>, the attribute value is updated. + * + * @param name the attribute name (<code>null</code> not permitted). + * @param value the value (<code>null</code> not permitted). + * + * @throws NullPointerException if either argument is <code>null</code>. + */ + public void addAttribute(Object name, Object value) + { + tab.put(name, value); + } + + /** + * Adds all the attributes from <code>attributes</code> to this set. + * + * @param attributes the set of attributes to add (<code>null</code> not + * permitted). + * + * @throws NullPointerException if <code>attributes</code> is + * <code>null</code>. + */ + public void addAttributes(AttributeSet attributes) + { + Enumeration e = attributes.getAttributeNames(); + while (e.hasMoreElements()) + { + Object name = e.nextElement(); + Object val = attributes.getAttribute(name); + tab.put(name, val); + } + } + + /** + * Returns a clone of the attribute set. + * + * @return A clone of the attribute set. + */ + public Object clone() + { + SimpleAttributeSet attr = null; + try + { + attr = (SimpleAttributeSet) super.clone(); + attr.tab = (Hashtable) tab.clone(); + } + catch (CloneNotSupportedException ex) + { + assert false; + } + return attr; + } + + /** + * Returns true if the given name and value represent an attribute + * found either in this AttributeSet or in its resolve parent hierarchy. + * @param name the key for the attribute + * @param value the value for the attribute + * @return true if the attribute is found here or in this set's resolve + * parent hierarchy + */ + public boolean containsAttribute(Object name, Object value) + { + if (value == null) + throw new NullPointerException("Null 'value' argument."); + if (tab.containsKey(name)) + return tab.get(name).equals(value); + else + { + AttributeSet p = getResolveParent(); + if (p != null) + return p.containsAttribute(name, value); + else + return false; + } + } + + /** + * Returns true if the given name and value are found in this AttributeSet. + * Does not check the resolve parent. + * @param name the key for the attribute + * @param value the value for the attribute + * @return true if the attribute is found in this AttributeSet + */ + boolean containsAttributeLocally(Object name, Object value) + { + return tab.containsKey(name) + && tab.get(name).equals(value); + } + + /** + * Returns <code>true</code> of this <code>AttributeSet</code> contains all + * of the specified <code>attributes</code>. + * + * @param attributes the requested attributes + * + * @return <code>true</code> of this <code>AttributeSet</code> contains all + * of the specified <code>attributes</code> + */ + public boolean containsAttributes(AttributeSet attributes) + { + Enumeration e = attributes.getAttributeNames(); + while (e.hasMoreElements()) + { + Object name = e.nextElement(); + Object val = attributes.getAttribute(name); + if (! containsAttribute(name, val)) + return false; + } + return true; + } + + /** + * Creates and returns a copy of this <code>AttributeSet</code>. + * + * @return a copy of this <code>AttributeSet</code> + */ + public AttributeSet copyAttributes() + { + return (AttributeSet) clone(); + } + + /** + * Checks this set for equality with an arbitrary object. + * + * @param obj the object (<code>null</code> permitted). + * + * @return <code>true</code> if this set is equal to <code>obj</code>, and + * <code>false</code> otherwise. + */ + public boolean equals(Object obj) + { + return + (obj instanceof AttributeSet) + && this.isEqual((AttributeSet) obj); + } + + /** + * Returns the value of the specified attribute, or <code>null</code> if + * there is no attribute with that name. If the attribute is not defined + * directly in this set, the parent hierarchy (if there is one) will be + * used. + * + * @param name the attribute (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>name</code> is <code>null</code>. + */ + public Object getAttribute(Object name) + { + Object val = tab.get(name); + if (val != null) + return val; + + AttributeSet p = getResolveParent(); + if (p != null) + return p.getAttribute(name); + + return null; + } + + /** + * Returns the number of attributes stored in this set, plus 1 if a parent + * has been specified (the reference to the parent is stored as a special + * attribute). The attributes stored in the parent do NOT contribute + * to the count. + * + * @return The attribute count. + */ + public int getAttributeCount() + { + return tab.size(); + } + + /** + * Returns an enumeration of the attribute names. + * + * @return An enumeration of the attribute names. + */ + public Enumeration<?> getAttributeNames() + { + return tab.keys(); + } + + /** + * Returns the resolving parent. + * + * @return The resolving parent (possibly <code>null</code>). + * + * @see #setResolveParent(AttributeSet) + */ + public AttributeSet getResolveParent() + { + return (AttributeSet) tab.get(ResolveAttribute); + } + + /** + * Returns a hash code for this instance. + * + * @return A hash code. + */ + public int hashCode() + { + return tab.hashCode(); + } + + /** + * Returns <code>true</code> if the given attribute is defined in this set, + * and <code>false</code> otherwise. The parent attribute set is not + * checked. + * + * @param attrName the attribute name (<code>null</code> not permitted). + */ + public boolean isDefined(Object attrName) + { + return tab.containsKey(attrName); + } + + /** + * Returns <code>true</code> if the set contains no attributes, and + * <code>false</code> otherwise. Note that the resolving parent is + * stored as an attribute, so this method will return <code>false</code> if + * a resolving parent is set. + * + * @return <code>true</code> if the set contains no attributes, and + * <code>false</code> otherwise. + */ + public boolean isEmpty() + { + return tab.isEmpty(); + } + + /** + * Returns true if the given set has the same number of attributes + * as this set and <code>containsAttributes(attr)</code> returns + * <code>true</code>. + * + * @param attr the attribute set (<code>null</code> not permitted). + * + * @return A boolean. + * + * @throws NullPointerException if <code>attr</code> is <code>null</code>. + */ + public boolean isEqual(AttributeSet attr) + { + return getAttributeCount() == attr.getAttributeCount() + && this.containsAttributes(attr); + } + + /** + * Removes the attribute with the specified <code>name</code>, if this + * attribute is defined. This method will only remove an attribute from + * this set, not from the resolving parent. + * + * @param name the attribute name (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>name</code> is <code>null</code>. + */ + public void removeAttribute(Object name) + { + tab.remove(name); + } + + /** + * Removes attributes from this set if they are found in the + * given set. Only attributes whose key AND value are removed. + * Removes attributes only from this set, not from the resolving parent. + * Since the resolving parent is stored as an attribute, if + * <code>attributes</code> has the same resolving parent as this set, the + * parent will be removed from this set. + * + * @param attributes the attributes (<code>null</code> not permitted). + */ + public void removeAttributes(AttributeSet attributes) + { + Enumeration e = attributes.getAttributeNames(); + while (e.hasMoreElements()) + { + Object name = e.nextElement(); + Object val = attributes.getAttribute(name); + if (containsAttributeLocally(name, val)) + removeAttribute(name); + } + } + + /** + * Removes the attributes listed in <code>names</code>. + * + * @param names the attribute names (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>names</code> is <code>null</code> + * or contains any <code>null</code> values. + */ + public void removeAttributes(Enumeration<?> names) + { + while (names.hasMoreElements()) + { + removeAttribute(names.nextElement()); + } + } + + /** + * Sets the reolving parent for this set. When looking up an attribute, if + * it is not found in this set, then the resolving parent is also used for + * the lookup. + * <p> + * Note that the parent is stored as an attribute, and will contribute 1 to + * the count returned by {@link #getAttributeCount()}. + * + * @param parent the parent attribute set (<code>null</code> not permitted). + * + * @throws NullPointerException if <code>parent</code> is <code>null</code>. + * + * @see #setResolveParent(AttributeSet) + */ + public void setResolveParent(AttributeSet parent) + { + addAttribute(ResolveAttribute, parent); + } + + /** + * Returns a string representation of this instance, typically used for + * debugging purposes. + * + * @return A string representation of this instance. + */ + public String toString() + { + return tab.toString(); + } +} |