/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* @author Oleg V. Khaschansky
*/
package com.google.code.appengine.awt.font;
import java.text.AttributedCharacterIterator;
import java.text.BreakIterator;
import org.apache.harmony.awt.internal.nls.Messages;
import com.google.code.appengine.awt.font.FontRenderContext;
import com.google.code.appengine.awt.font.TextLayout;
import com.google.code.appengine.awt.font.TextMeasurer;
public final class LineBreakMeasurer {
private TextMeasurer tm = null;
private BreakIterator bi = null;
private int position = 0;
int maxpos = 0;
public LineBreakMeasurer(AttributedCharacterIterator text, FontRenderContext frc) {
this(text, BreakIterator.getLineInstance(), frc);
}
public LineBreakMeasurer(
AttributedCharacterIterator text,
BreakIterator bi,
FontRenderContext frc
) {
tm = new TextMeasurer(text, frc);
this.bi = bi;
this.bi.setText(text);
position = text.getBeginIndex();
maxpos = tm.aci.getEndIndex();
}
public void deleteChar(AttributedCharacterIterator newText, int pos) {
tm.deleteChar(newText, pos);
bi.setText(newText);
position = newText.getBeginIndex();
maxpos--;
}
public int getPosition() {
return position;
}
public void insertChar(AttributedCharacterIterator newText, int pos) {
tm.insertChar(newText, pos);
bi.setText(newText);
position = newText.getBeginIndex();
maxpos++;
}
public TextLayout nextLayout(float wrappingWidth, int offsetLimit, boolean requireNextWord) {
if (position == maxpos) {
return null;
}
int nextPosition = nextOffset(wrappingWidth, offsetLimit, requireNextWord);
if (nextPosition == position) {
return null;
}
TextLayout layout = tm.getLayout(position, nextPosition);
position = nextPosition;
return layout;
}
public TextLayout nextLayout(float wrappingWidth) {
return nextLayout(wrappingWidth, maxpos, false);
}
public int nextOffset(float wrappingWidth) {
return nextOffset(wrappingWidth, maxpos, false);
}
public int nextOffset(float wrappingWidth, int offsetLimit, boolean requireNextWord) {
if (offsetLimit <= position) {
// awt.203=Offset limit should be greater than current position.
throw new IllegalArgumentException(Messages.getString("awt.203")); //$NON-NLS-1$
}
if (position == maxpos) {
return position;
}
int breakPos = tm.getLineBreakIndex(position, wrappingWidth);
int correctedPos = breakPos;
// This check is required because bi.preceding(maxpos) throws an exception
if (breakPos == maxpos) {
correctedPos = maxpos;
} else if (Character.isWhitespace(bi.getText().setIndex(breakPos))) {
correctedPos = bi.following(breakPos);
} else {
correctedPos = bi.preceding(breakPos);
}
if (position >= correctedPos) {
if (requireNextWord) {
correctedPos = position;
} else {
correctedPos = Math.max(position+1, breakPos);
}
}
return Math.min(correctedPos, offsetLimit);
}
public void setPosition(int pos) {
if (tm.aci.getBeginIndex() > pos || maxpos < pos) {
// awt.33=index is out of range
throw new IllegalArgumentException(Messages.getString("awt.33")); //$NON-NLS-1$
}
position = pos;
}
}