// AttributesImpl.java - default implementation of Attributes.
// http://www.saxproject.org
// Written by David Megginson
// NO WARRANTY!  This class is in the public domain.
// $Id: AttributesImpl.java 226184 2005-04-08 10:53:24Z neeraj $

package org.xml.sax.helpers;

import org.xml.sax.Attributes;


Default implementation of the Attributes interface.
This module, both source code and documentation, is in the Public Domain, and comes with NO WARRANTY. See http://www.saxproject.org for further information.

This class provides a default implementation of the SAX2 Attributes interface, with the addition of manipulators so that the list can be modified or reused.

There are two typical uses of this class:

  1. to take a persistent snapshot of an Attributes object in a startElement event; or
  2. to construct or modify an Attributes object in a SAX2 driver or filter.

This class replaces the now-deprecated SAX1 AttributeListImpl class; in addition to supporting the updated Attributes interface rather than the deprecated AttributeList interface, it also includes a much more efficient implementation using a single array rather than a set of Vectors.

Author:David Megginson
Since:SAX 2.0
Version:2.0.1 (sax2r2)
/** * Default implementation of the Attributes interface. * * <blockquote> * <em>This module, both source code and documentation, is in the * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> * for further information. * </blockquote> * * <p>This class provides a default implementation of the SAX2 * {@link org.xml.sax.Attributes Attributes} interface, with the * addition of manipulators so that the list can be modified or * reused.</p> * * <p>There are two typical uses of this class:</p> * * <ol> * <li>to take a persistent snapshot of an Attributes object * in a {@link org.xml.sax.ContentHandler#startElement startElement} event; or</li> * <li>to construct or modify an Attributes object in a SAX2 driver or filter.</li> * </ol> * * <p>This class replaces the now-deprecated SAX1 {@link * org.xml.sax.helpers.AttributeListImpl AttributeListImpl} * class; in addition to supporting the updated Attributes * interface rather than the deprecated {@link org.xml.sax.AttributeList * AttributeList} interface, it also includes a much more efficient * implementation using a single array rather than a set of Vectors.</p> * * @since SAX 2.0 * @author David Megginson * @version 2.0.1 (sax2r2) */
public class AttributesImpl implements Attributes { //////////////////////////////////////////////////////////////////// // Constructors. ////////////////////////////////////////////////////////////////////
Construct a new, empty AttributesImpl object.
/** * Construct a new, empty AttributesImpl object. */
public AttributesImpl () { length = 0; data = null; }
Copy an existing Attributes object.

This constructor is especially useful inside a startElement event.

Params:
  • atts – The existing Attributes object.
/** * Copy an existing Attributes object. * * <p>This constructor is especially useful inside a * {@link org.xml.sax.ContentHandler#startElement startElement} event.</p> * * @param atts The existing Attributes object. */
public AttributesImpl (Attributes atts) { setAttributes(atts); } //////////////////////////////////////////////////////////////////// // Implementation of org.xml.sax.Attributes. ////////////////////////////////////////////////////////////////////
Return the number of attributes in the list.
See Also:
Returns:The number of attributes in the list.
/** * Return the number of attributes in the list. * * @return The number of attributes in the list. * @see org.xml.sax.Attributes#getLength */
public int getLength () { return length; }
Return an attribute's Namespace URI.
Params:
  • index – The attribute's index (zero-based).
See Also:
Returns:The Namespace URI, the empty string if none is available, or null if the index is out of range.
/** * Return an attribute's Namespace URI. * * @param index The attribute's index (zero-based). * @return The Namespace URI, the empty string if none is * available, or null if the index is out of range. * @see org.xml.sax.Attributes#getURI */
public String getURI (int index) { if (index >= 0 && index < length) { return data[index*5]; } else { return null; } }
Return an attribute's local name.
Params:
  • index – The attribute's index (zero-based).
See Also:
Returns:The attribute's local name, the empty string if none is available, or null if the index if out of range.
/** * Return an attribute's local name. * * @param index The attribute's index (zero-based). * @return The attribute's local name, the empty string if * none is available, or null if the index if out of range. * @see org.xml.sax.Attributes#getLocalName */
public String getLocalName (int index) { if (index >= 0 && index < length) { return data[index*5+1]; } else { return null; } }
Return an attribute's qualified (prefixed) name.
Params:
  • index – The attribute's index (zero-based).
See Also:
Returns:The attribute's qualified name, the empty string if none is available, or null if the index is out of bounds.
/** * Return an attribute's qualified (prefixed) name. * * @param index The attribute's index (zero-based). * @return The attribute's qualified name, the empty string if * none is available, or null if the index is out of bounds. * @see org.xml.sax.Attributes#getQName */
public String getQName (int index) { if (index >= 0 && index < length) { return data[index*5+2]; } else { return null; } }
Return an attribute's type by index.
Params:
  • index – The attribute's index (zero-based).
See Also:
Returns:The attribute's type, "CDATA" if the type is unknown, or null if the index is out of bounds.
/** * Return an attribute's type by index. * * @param index The attribute's index (zero-based). * @return The attribute's type, "CDATA" if the type is unknown, or null * if the index is out of bounds. * @see org.xml.sax.Attributes#getType(int) */
public String getType (int index) { if (index >= 0 && index < length) { return data[index*5+3]; } else { return null; } }
Return an attribute's value by index.
Params:
  • index – The attribute's index (zero-based).
See Also:
Returns:The attribute's value or null if the index is out of bounds.
/** * Return an attribute's value by index. * * @param index The attribute's index (zero-based). * @return The attribute's value or null if the index is out of bounds. * @see org.xml.sax.Attributes#getValue(int) */
public String getValue (int index) { if (index >= 0 && index < length) { return data[index*5+4]; } else { return null; } }
Look up an attribute's index by Namespace name.

In many cases, it will be more efficient to look up the name once and use the index query methods rather than using the name query methods repeatedly.

Params:
  • uri – The attribute's Namespace URI, or the empty string if none is available.
  • localName – The attribute's local name.
See Also:
Returns:The attribute's index, or -1 if none matches.
/** * Look up an attribute's index by Namespace name. * * <p>In many cases, it will be more efficient to look up the name once and * use the index query methods rather than using the name query methods * repeatedly.</p> * * @param uri The attribute's Namespace URI, or the empty * string if none is available. * @param localName The attribute's local name. * @return The attribute's index, or -1 if none matches. * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String) */
public int getIndex (String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i+1].equals(localName)) { return i / 5; } } return -1; }
Look up an attribute's index by qualified (prefixed) name.
Params:
  • qName – The qualified name.
See Also:
Returns:The attribute's index, or -1 if none matches.
/** * Look up an attribute's index by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's index, or -1 if none matches. * @see org.xml.sax.Attributes#getIndex(java.lang.String) */
public int getIndex (String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i+2].equals(qName)) { return i / 5; } } return -1; }
Look up an attribute's type by Namespace-qualified name.
Params:
  • uri – The Namespace URI, or the empty string for a name with no explicit Namespace URI.
  • localName – The local name.
See Also:
Returns:The attribute's type, or null if there is no matching attribute.
/** * Look up an attribute's type by Namespace-qualified name. * * @param uri The Namespace URI, or the empty string for a name * with no explicit Namespace URI. * @param localName The local name. * @return The attribute's type, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getType(java.lang.String,java.lang.String) */
public String getType (String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i+1].equals(localName)) { return data[i+3]; } } return null; }
Look up an attribute's type by qualified (prefixed) name.
Params:
  • qName – The qualified name.
See Also:
Returns:The attribute's type, or null if there is no matching attribute.
/** * Look up an attribute's type by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's type, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getType(java.lang.String) */
public String getType (String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i+2].equals(qName)) { return data[i+3]; } } return null; }
Look up an attribute's value by Namespace-qualified name.
Params:
  • uri – The Namespace URI, or the empty string for a name with no explicit Namespace URI.
  • localName – The local name.
See Also:
Returns:The attribute's value, or null if there is no matching attribute.
/** * Look up an attribute's value by Namespace-qualified name. * * @param uri The Namespace URI, or the empty string for a name * with no explicit Namespace URI. * @param localName The local name. * @return The attribute's value, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getValue(java.lang.String,java.lang.String) */
public String getValue (String uri, String localName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i].equals(uri) && data[i+1].equals(localName)) { return data[i+4]; } } return null; }
Look up an attribute's value by qualified (prefixed) name.
Params:
  • qName – The qualified name.
See Also:
Returns:The attribute's value, or null if there is no matching attribute.
/** * Look up an attribute's value by qualified (prefixed) name. * * @param qName The qualified name. * @return The attribute's value, or null if there is no * matching attribute. * @see org.xml.sax.Attributes#getValue(java.lang.String) */
public String getValue (String qName) { int max = length * 5; for (int i = 0; i < max; i += 5) { if (data[i+2].equals(qName)) { return data[i+4]; } } return null; } //////////////////////////////////////////////////////////////////// // Manipulators. ////////////////////////////////////////////////////////////////////
Clear the attribute list for reuse.

Note that little memory is freed by this call: the current array is kept so it can be reused.

/** * Clear the attribute list for reuse. * * <p>Note that little memory is freed by this call: * the current array is kept so it can be * reused.</p> */
public void clear () { if (data != null) { for (int i = 0; i < (length * 5); i++) data [i] = null; } length = 0; }
Copy an entire Attributes object.

It may be more efficient to reuse an existing object rather than constantly allocating new ones.

Params:
  • atts – The attributes to copy.
/** * Copy an entire Attributes object. * * <p>It may be more efficient to reuse an existing object * rather than constantly allocating new ones.</p> * * @param atts The attributes to copy. */
public void setAttributes (Attributes atts) { clear(); length = atts.getLength(); if (length > 0) { data = new String[length*5]; for (int i = 0; i < length; i++) { data[i*5] = atts.getURI(i); data[i*5+1] = atts.getLocalName(i); data[i*5+2] = atts.getQName(i); data[i*5+3] = atts.getType(i); data[i*5+4] = atts.getValue(i); } } }
Add an attribute to the end of the list.

For the sake of speed, this method does no checking to see if the attribute is already in the list: that is the responsibility of the application.

Params:
  • uri – The Namespace URI, or the empty string if none is available or Namespace processing is not being performed.
  • localName – The local name, or the empty string if Namespace processing is not being performed.
  • qName – The qualified (prefixed) name, or the empty string if qualified names are not available.
  • type – The attribute type as a string.
  • value – The attribute value.
/** * Add an attribute to the end of the list. * * <p>For the sake of speed, this method does no checking * to see if the attribute is already in the list: that is * the responsibility of the application.</p> * * @param uri The Namespace URI, or the empty string if * none is available or Namespace processing is not * being performed. * @param localName The local name, or the empty string if * Namespace processing is not being performed. * @param qName The qualified (prefixed) name, or the empty string * if qualified names are not available. * @param type The attribute type as a string. * @param value The attribute value. */
public void addAttribute (String uri, String localName, String qName, String type, String value) { ensureCapacity(length+1); data[length*5] = uri; data[length*5+1] = localName; data[length*5+2] = qName; data[length*5+3] = type; data[length*5+4] = value; length++; }
Set an attribute in the list.

For the sake of speed, this method does no checking for name conflicts or well-formedness: such checks are the responsibility of the application.

Params:
  • index – The index of the attribute (zero-based).
  • uri – The Namespace URI, or the empty string if none is available or Namespace processing is not being performed.
  • localName – The local name, or the empty string if Namespace processing is not being performed.
  • qName – The qualified name, or the empty string if qualified names are not available.
  • type – The attribute type as a string.
  • value – The attribute value.
Throws:
/** * Set an attribute in the list. * * <p>For the sake of speed, this method does no checking * for name conflicts or well-formedness: such checks are the * responsibility of the application.</p> * * @param index The index of the attribute (zero-based). * @param uri The Namespace URI, or the empty string if * none is available or Namespace processing is not * being performed. * @param localName The local name, or the empty string if * Namespace processing is not being performed. * @param qName The qualified name, or the empty string * if qualified names are not available. * @param type The attribute type as a string. * @param value The attribute value. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setAttribute (int index, String uri, String localName, String qName, String type, String value) { if (index >= 0 && index < length) { data[index*5] = uri; data[index*5+1] = localName; data[index*5+2] = qName; data[index*5+3] = type; data[index*5+4] = value; } else { badIndex(index); } }
Remove an attribute from the list.
Params:
  • index – The index of the attribute (zero-based).
Throws:
/** * Remove an attribute from the list. * * @param index The index of the attribute (zero-based). * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void removeAttribute (int index) { if (index >= 0 && index < length) { if (index < length - 1) { System.arraycopy(data, (index+1)*5, data, index*5, (length-index-1)*5); } index = (length - 1) * 5; data [index++] = null; data [index++] = null; data [index++] = null; data [index++] = null; data [index] = null; length--; } else { badIndex(index); } }
Set the Namespace URI of a specific attribute.
Params:
  • index – The index of the attribute (zero-based).
  • uri – The attribute's Namespace URI, or the empty string for none.
Throws:
/** * Set the Namespace URI of a specific attribute. * * @param index The index of the attribute (zero-based). * @param uri The attribute's Namespace URI, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setURI (int index, String uri) { if (index >= 0 && index < length) { data[index*5] = uri; } else { badIndex(index); } }
Set the local name of a specific attribute.
Params:
  • index – The index of the attribute (zero-based).
  • localName – The attribute's local name, or the empty string for none.
Throws:
/** * Set the local name of a specific attribute. * * @param index The index of the attribute (zero-based). * @param localName The attribute's local name, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setLocalName (int index, String localName) { if (index >= 0 && index < length) { data[index*5+1] = localName; } else { badIndex(index); } }
Set the qualified name of a specific attribute.
Params:
  • index – The index of the attribute (zero-based).
  • qName – The attribute's qualified name, or the empty string for none.
Throws:
/** * Set the qualified name of a specific attribute. * * @param index The index of the attribute (zero-based). * @param qName The attribute's qualified name, or the empty * string for none. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setQName (int index, String qName) { if (index >= 0 && index < length) { data[index*5+2] = qName; } else { badIndex(index); } }
Set the type of a specific attribute.
Params:
  • index – The index of the attribute (zero-based).
  • type – The attribute's type.
Throws:
/** * Set the type of a specific attribute. * * @param index The index of the attribute (zero-based). * @param type The attribute's type. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setType (int index, String type) { if (index >= 0 && index < length) { data[index*5+3] = type; } else { badIndex(index); } }
Set the value of a specific attribute.
Params:
  • index – The index of the attribute (zero-based).
  • value – The attribute's value.
Throws:
/** * Set the value of a specific attribute. * * @param index The index of the attribute (zero-based). * @param value The attribute's value. * @exception java.lang.ArrayIndexOutOfBoundsException When the * supplied index does not point to an attribute * in the list. */
public void setValue (int index, String value) { if (index >= 0 && index < length) { data[index*5+4] = value; } else { badIndex(index); } } //////////////////////////////////////////////////////////////////// // Internal methods. ////////////////////////////////////////////////////////////////////
Ensure the internal array's capacity.
Params:
  • n – The minimum number of attributes that the array must be able to hold.
/** * Ensure the internal array's capacity. * * @param n The minimum number of attributes that the array must * be able to hold. */
private void ensureCapacity (int n) { if (n <= 0) { return; } int max; if (data == null || data.length == 0) { max = 25; } else if (data.length >= n * 5) { return; } else { max = data.length; } while (max < n * 5) { max *= 2; } String newData[] = new String[max]; if (length > 0) { System.arraycopy(data, 0, newData, 0, length*5); } data = newData; }
Report a bad array index in a manipulator.
Params:
  • index – The index to report.
Throws:
/** * Report a bad array index in a manipulator. * * @param index The index to report. * @exception java.lang.ArrayIndexOutOfBoundsException Always. */
private void badIndex (int index) throws ArrayIndexOutOfBoundsException { String msg = "Attempt to modify attribute at illegal index: " + index; throw new ArrayIndexOutOfBoundsException(msg); } //////////////////////////////////////////////////////////////////// // Internal state. //////////////////////////////////////////////////////////////////// int length; String data []; } // end of AttributesImpl.java