[cp-patches] FYI: Added DefaultFormatter class to javax.swing.text

[Roman Kennke]

In order to get the missing JSpinner editors straight, I implemented the 
DefaultFormatter class in javax.swing.text.

2005-06-06  Roman Kennke  <address@hidden>

   * javax/swing/text/DefaultFormatter.java:
   Implemented new class.

/Roman

Index: javax/swing/text/DefaultFormatter.java
===================================================================
RCS file: javax/swing/text/DefaultFormatter.java
diff -N javax/swing/text/DefaultFormatter.java
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ javax/swing/text/DefaultFormatter.java      6 Jun 2005 15:16:37 -0000
@@ -0,0 +1,390 @@
+/* DefaultFormatter.java --
+Copyright (C) 2005  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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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.lang.reflect.Constructor;
+import java.text.ParseException;
+
+import javax.swing.JFormattedTextField;
+
+/**
+ * The <code>DefaultFormatter</code> is a concrete formatter for use in
+ * address@hidden JFormattedTextField}s.
+ *
+ * It can format arbitrary values by invoking
+ * their address@hidden Object#toString} method.
+ *
+ * In order to convert a String back to
+ * a value, the value class must provide a single argument constructor that
+ * takes a String object as argument value. If no such constructor is found,
+ * the String itself is passed back by #stringToValue.
+ *  
+ * @author Roman Kennke (address@hidden)
+ */
+public class DefaultFormatter
+  extends JFormattedTextField.AbstractFormatter
+  implements Cloneable, Serializable
+{
+
+  /**
+   * A address@hidden DocumentFilter} that intercepts modification of the
+   * JFormattedTextField's Document and commits the value depending
+   * on the value of the <code>commitsOnValidEdit</code> property.
+   *
+   */
+  // FIXME: Handle allowsInvalid and overwriteMode properties
+  private class FormatterDocumentFilter
+    extends DocumentFilter
+  {
+    /**
+     * Invoked when text is removed from a text component.
+     *
+     * @param bypass the FilterBypass to use to mutate the document
+     * @param offset the start position of the modification
+     * @param length the length of the removed text
+     *
+     * @throws BadLocationException if offset or lenght are invalid in
+     *     the Document
+     */
+    public void remove(DocumentFilter.FilterBypass bypass, int offset,
+                        int length)
+      throws BadLocationException
+    {
+      super.remove(bypass, offset, length);
+      commitIfAllowed();
+    }
+    
+    /**
+     * Invoked when text is inserted into a text component.
+     *
+     * @param bypass the FilterBypass to use to mutate the document
+     * @param offset the start position of the modification
+     * @param text the inserted text
+     * @param attributes the attributes of the inserted text
+     *
+     * @throws BadLocationException if offset or lenght are invalid in
+     *     the Document
+     */
+    public void insertString(DocumentFilter.FilterBypass bypass, int offset,
+                              String text, AttributeSet attributes)
+      throws BadLocationException
+    {
+      super.insertString(bypass, offset, text, attributes);
+      commitIfAllowed();
+    }
+
+    /**
+     * Invoked when text is replaced in a text component.
+     * 
+     * @param bypass the FilterBypass to use to mutate the document
+     * @param offset the start position of the modification
+     * @param length the length of the removed text
+     * @param text the inserted text
+     * @param attributes the attributes of the inserted text
+     *
+     * @throws BadLocationException if offset or lenght are invalid in
+     *     the Document
+     */
+    public void replace(DocumentFilter.FilterBypass bypass, int offset,
+                         int length, String text, AttributeSet attributes)
+      throws BadLocationException
+    {
+      super.replace(bypass, offset, length, text, attributes);
+      commitIfAllowed();
+    }
+
+    /**
+     * Commits the value to the JTextTextField if the property
+     * <code>commitsOnValidEdit</code> is set to <code>true</code>.
+     */
+    private void commitIfAllowed()
+    {
+      if (commitsOnValidEdit == true)
+        try
+          {
+            getFormattedTextField().commitEdit();
+          }
+        catch (ParseException ex)
+          {
+            // ignore invalid edits
+          }
+    }
+  }
+
+  /** The serialVersoinUID. */
+  private static final long serialVersionUID = -7369196326612908900L;
+
+  /**
+   * Indicates if the value should be committed after every
+   * valid modification of the Document.
+   */
+  boolean commitsOnValidEdit;
+
+  /**
+   * If <code>true</code> newly inserted characters overwrite existing
+   * values, otherwise insertion is done the normal way.
+   */
+  boolean overwriteMode;
+
+  /**
+   * If <code>true</code> invalid edits are allowed for a limited
+   * time.
+   */
+  boolean allowsInvalid;
+
+  /**
+   * The class that is used for values.
+   */
+  Class valueClass;
+
+  /**
+   * Creates a new instance of <code>DefaultFormatter</code>.
+   */
+  public DefaultFormatter()
+  {
+    commitsOnValidEdit = true;
+    overwriteMode = true;
+    allowsInvalid = true;
+    valueClass = Object.class;
+  }
+
+  /**
+   * Installs the formatter on the specified address@hidden 
JFormattedTextField}.
+   *
+   * This method does the following things:
+   * <ul>
+   * <li>Display the value of #valueToString in the
+   *  <code>JFormattedTextField</code></li>
+   * <li>Install the Actions from #getActions on the <code>JTextField</code>
+   * </li>
+   * <li>Install the DocumentFilter returned by #getDocumentFilter</li>
+   * <li>Install the NavigationFilter returned by #getNavigationFilter</li>
+   * </ul>
+   *
+   * This method is typically not overridden by subclasses. Instead override
+   * one of the mentioned methods in order to customize behaviour.
+   *
+   * @param ftf the address@hidden JFormattedTextField} in which this formatter
+   *     is installed 
+   */
+  public void install(JFormattedTextField ftf)
+  {
+    super.install(ftf);
+  }
+
+  /**
+   * Returns <code>true</code> if the value should be committed after
+   * each valid modification of the input field, <code>false</code> if
+   * it should never be committed by this formatter.
+   *
+   * @return the state of the <code>commitsOnValidEdit</code> property
+   *
+   * @see #setCommitsOnValidEdit
+   */
+  public boolean getCommitsOnValidEdit()
+  {
+    return commitsOnValidEdit;
+  }
+
+  /**
+   * Sets the value of the <code>commitsOnValidEdit</code> property.
+   *
+   * @param commitsOnValidEdit the new state of the
+   *     <code>commitsOnValidEdit</code> property
+   *
+   * @see #getCommitsOnValidEdit
+   */
+  public void setCommitsOnValidEdit(boolean commitsOnValidEdit)
+  {
+    this.commitsOnValidEdit = commitsOnValidEdit;
+  }
+
+  /**
+   * Returns the value of the <code>overwriteMode</code> property.
+   * If that is set to <code>true</code> then newly inserted characters
+   * overwrite existing values, otherwise the characters are inserted like
+   * normal. The default is <code>true</code>.
+   *
+   * @return the value of the <code>overwriteMode</code> property
+   */
+  public boolean getOverwriteMode()
+  {
+    return overwriteMode;
+  }
+
+  /**
+   * Sets the value of the <code>overwriteMode</code> property.
+   * 
+   * If that is set to <code>true</code> then newly inserted characters
+   * overwrite existing values, otherwise the characters are inserted like
+   * normal. The default is <code>true</code>.
+   *
+   * @param overwriteMode the new value for the <code>overwriteMode</code>
+   *     property
+   */
+  public void setOverwriteMode(boolean overwriteMode)
+  {
+    this.overwriteMode = overwriteMode;
+  }
+
+  /**
+   * Returns whether or not invalid edits are allowed or not. If invalid
+   * edits are allowed, the JFormattedTextField may temporarily contain invalid
+   * characters.
+   *
+   * @return the value of the allowsInvalid property
+   */
+  public boolean getAllowsInvalid()
+  {
+    return allowsInvalid;
+  }
+
+  /**
+   * Sets the value of the <code>allowsInvalid</code> property.
+   *
+   * @param allowsInvalid the new value for the property
+   *
+   * @see #getAllowsInvalid()
+   */
+  public void setAllowsInvalid(boolean allowsInvalid)
+  {
+    this.allowsInvalid = allowsInvalid;
+  }
+
+  /**
+   * Returns the class that is used for values. When Strings are converted
+   * back to values, this class is used to create new value objects.
+   *
+   * @return the class that is used for values
+   */
+  public Class getValueClass()
+  {
+    return valueClass;
+  }
+
+  /**
+   * Sets the class that is used for values.
+   *
+   * @param valueClass the class that is used for values
+   *
+   * @see #getValueClass()
+   */
+  public void setValueClass(Class valueClass)
+  {
+    this.valueClass = valueClass;
+  }
+
+  /**
+   * Converts a String (from the JFormattedTextField input) to a value.
+   * In order to achieve this, the formatter tries to instantiate an object
+   * of the class returned by #getValueClass() using a single argument
+   * constructor that takes a String argument. If such a constructor cannot
+   * be found, the String itself is returned.
+   *
+   * @param string the string to convert
+   *
+   * @return the value for the string
+   *
+   * @throws ParseException if the string cannot be converted into
+   *     a value object (e.g. invalid input)
+   */
+  public Object stringToValue(String string)
+    throws ParseException
+  {
+    Object value = string;
+    Class valueClass = getValueClass();
+    if (valueClass == null)
+      valueClass = getFormattedTextField().getValue().getClass();
+    if (valueClass != null)
+      try
+        {
+          Constructor constr = valueClass.getConstructor
+                                             (new Class[]{String.class});
+          value = constr.newInstance(new Object[]{ string });
+        }
+      catch (NoSuchMethodException ex)
+        {
+          // leave value as string
+        }
+      catch (Exception ex)
+        {
+          throw new ParseException(string, 0);
+        }
+    return value;
+  }
+
+  /**
+   * Converts a value object into a String. This is done by invoking the
+   * address@hidden Object#toString()} method on the value.
+   *
+   * @param value the value to be converted
+   *
+   * @return the string representation of the value
+   *
+   * @throws ParseException if the value cannot be converted
+   */
+  public String valueToString(Object value)
+    throws ParseException
+  {
+    return value.toString();
+  }
+
+  /**
+   * Creates and returns a clone of this DefaultFormatter.
+   *
+   * @return a clone of this object
+   *
+   * @throws CloneNotSupportedException not thrown here
+   */
+  public Object clone()
+    throws CloneNotSupportedException
+  {
+    return super.clone();
+  }
+
+  /**
+   * Returns the DocumentFilter that is used to restrict input.
+   *
+   * @return the DocumentFilter that is used to restrict input
+   */
+  protected DocumentFilter getDocumentFilter()
+  {
+    return new FormatterDocumentFilter();
+  }
+}