+ * 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 + * {@link org.xml.sax.Attributes Attributes} interface, with the + * addition of manipulators so that the list can be modified or + * reused.
+ * + *There are two typical uses of this class:
+ * + *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.
+ * + * @since SAX 2.0 + * @author David Megginson + * @version 2.0.1 (sax2r2) + */ +public class AttributesImpl implements Attributes +{ + + + //////////////////////////////////////////////////////////////////// + // Constructors. + //////////////////////////////////////////////////////////////////// + + + /** + * Construct a new, empty AttributesImpl object. + */ + public AttributesImpl () + { + length = 0; + data = null; + } + + + /** + * Copy an existing Attributes object. + * + *This constructor is especially useful inside a + * {@link org.xml.sax.ContentHandler#startElement startElement} event.
+ * + * @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. + * + * @return The number of attributes in the list. + * @see org.xml.sax.Attributes#getLength + */ + @Override + public int getLength () + { + return length; + } + + + /** + * 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 + */ + @Override + public String getURI (int index) + { + if (index >= 0 && index < length) { + return data[index*5]; + } else { + return null; + } + } + + + /** + * 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 + */ + @Override + 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. + * + * @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 + */ + @Override + 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. + * + * @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) + */ + @Override + 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. + * + * @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) + */ + @Override + 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.
+ * + * @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) + */ + @Override + 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. + * + * @param qName The qualified name. + * @return The attribute's index, or -1 if none matches. + * @see org.xml.sax.Attributes#getIndex(java.lang.String) + */ + @Override + 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. + * + * @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) + */ + @Override + 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. + * + * @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) + */ + @Override + 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. + * + * @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) + */ + @Override + 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. + * + * @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) + */ + @Override + 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.
+ */ + 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.
+ * + * @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.
+ * + * @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.
+ * + * @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. + * + * @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. + * + * @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. + * + * @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. + * + * @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. + * + * @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. + * + * @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. + * + * @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. + * + * @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 +