org.apache.xmlgraphics.ps.FormGenerator Maven / Gradle / Ivy
/*
* 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.
*/
/* $Id: FormGenerator.java 750418 2009-03-05 11:03:54Z vhennebert $ */
package org.apache.xmlgraphics.ps;
import java.awt.geom.AffineTransform;
import java.awt.geom.Dimension2D;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
/**
* Abstract helper class for generating PostScript forms.
*/
public abstract class FormGenerator {
private String formName;
private String title;
private Dimension2D dimensions;
/**
* Main constructor.
* @param formName the form's name
* @param title the form's title or null
* @param dimensions the form's dimensions
*/
public FormGenerator(String formName, String title, Dimension2D dimensions) {
this.formName = formName;
this.title = title;
this.dimensions = dimensions;
}
/**
* Returns the form's name.
* @return the form's name
*/
public String getFormName() {
return this.formName;
}
/**
* Returns the form's title.
* @return the form's title or null if there's no title
*/
public String getTitle() {
return this.title;
}
/**
* returns the form's dimensions.
* @return the form's dimensions
*/
public Dimension2D getDimensions() {
return this.dimensions;
}
/**
* Generates the PostScript code for the PaintProc of the form.
* @param gen the PostScript generator
* @throws IOException if an I/O error occurs
*/
protected abstract void generatePaintProc(PSGenerator gen) throws IOException;
/**
* Generates some PostScript code right after the form definition (used primarily for
* bitmap data).
* @param gen the PostScript generator
* @throws IOException if an I/O error occurs
*/
protected void generateAdditionalDataStream(PSGenerator gen) throws IOException {
//nop
}
/**
* Returns the matrix for use in the form.
* @return the matrix
*/
protected AffineTransform getMatrix() {
return new AffineTransform();
}
/**
* Returns the form's bounding box.
* @return the form's bounding box
*/
protected Rectangle2D getBBox() {
return new Rectangle2D.Double(0, 0, dimensions.getWidth(), dimensions.getHeight());
}
/**
* Generates the PostScript form.
* @param gen the PostScript generator
* @return a PSResource instance representing the form
* @throws IOException if an I/O error occurs
*/
public PSResource generate(PSGenerator gen) throws IOException {
if (gen.getPSLevel() < 2) {
throw new UnsupportedOperationException(
"Forms require at least Level 2 PostScript");
}
gen.writeDSCComment(DSCConstants.BEGIN_RESOURCE,
new Object[] {PSResource.TYPE_FORM, getFormName()});
if (title != null) {
gen.writeDSCComment(DSCConstants.TITLE, title);
}
gen.writeln("/" + formName);
gen.writeln("<< /FormType 1");
gen.writeln(" /BBox " + gen.formatRectangleToArray(getBBox()));
gen.writeln(" /Matrix " + gen.formatMatrix(getMatrix()));
gen.writeln(" /PaintProc {");
gen.writeln(" pop");
gen.writeln(" gsave");
generatePaintProc(gen);
gen.writeln(" grestore");
gen.writeln(" } bind");
gen.writeln(">> def");
generateAdditionalDataStream(gen);
gen.writeDSCComment(DSCConstants.END_RESOURCE);
PSResource res = new PSResource(PSResource.TYPE_FORM, formName);
gen.getResourceTracker().registerSuppliedResource(res);
return res;
}
}