/*
* 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.
*/
/* $Id$ */
package org.apache.fop.render.ps.fonts;
import java.io.IOException;
import org.apache.xmlgraphics.ps.PSGenerator;
import org.apache.xmlgraphics.util.io.ASCIIHexOutputStream;
/**
* This is a wrapper for {@link PSGenerator} that contains some members specific for streaming
* TrueType fonts to a PostScript document.
*/
public class PSTTFGenerator {
private PSGenerator gen;
private ASCIIHexOutputStream hexOut;
/**
* The buffer is used to store the font file in an array of hex-encoded strings. Strings are
* limited to 65535 characters, string will start with a newline, 2 characters are needed to
* hex-encode each byte.
*/
public static final int MAX_BUFFER_SIZE = 32764;
/**
* Creates a new instance wrapping the given generator.
* @param gen the PSGenerator to wrap
*/
public PSTTFGenerator(PSGenerator gen) {
this.gen = gen;
hexOut = new ASCIIHexOutputStream(gen.getOutputStream());
}
/**
* Writes the '<' character that starts a string.
*/
public void startString() throws IOException {
// We need to reset the streamer so that it starts a new line in the PS document
hexOut = new ASCIIHexOutputStream(gen.getOutputStream());
gen.writeln("<");
}
/**
* Writes the given string to the output.
* @param cmd a string
*/
public void write(String cmd) throws IOException {
gen.write(cmd);
}
/**
* Writes the given string to the output, followed by a newline.
* @param cmd a string
*/
public void writeln(String cmd) throws IOException {
gen.writeln(cmd);
}
/**
* Writes bytes from the given byte array to the output.
*
* @param byteArray byte[] a byte array
* @param offset the position in the byte array where the streaming must start
* @param length the number of bytes to stream. This MUST be less than
* {@link #MAX_BUFFER_SIZE} - 1 since strings are suffixed by '00' (see Section 4.2 of
* Adobe Technical Note #5012, <em>The Type 42 Font Format Specification</em>.).
*/
public void streamBytes(byte[] byteArray, int offset, int length) throws IOException {
if (length > MAX_BUFFER_SIZE) {
throw new UnsupportedOperationException("Attempting to write a string to a PostScript"
+ " file that is greater than the buffer size.");
}
hexOut.write(byteArray, offset, length);
}
/**
* Finishes writing a string by appending '00' and '>' to the end.
*/
public void endString() throws IOException {
/* Appends a '00' to the end of the string as specified in the spec */
gen.write("00\n> ");
}
}