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PlantUML is a component that allows to quickly write diagrams from text.
// THIS FILE HAS BEEN GENERATED BY A PREPROCESSOR.
/* +=======================================================================
* |
* | PlantUML : a free UML diagram generator
* |
* +=======================================================================
*
* (C) Copyright 2009-2024, Arnaud Roques
*
* Project Info: https://plantuml.com
*
* If you like this project or if you find it useful, you can support us at:
*
* https://plantuml.com/patreon (only 1$ per month!)
* https://plantuml.com/liberapay (only 1€ per month!)
* https://plantuml.com/paypal
*
*
* PlantUML is free software; you can redistribute it and/or modify it
* under the terms of the Eclipse Public License.
*
* THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE PUBLIC
* LICENSE ("AGREEMENT"). [Eclipse Public License - v 1.0]
*
* ANY USE, REPRODUCTION OR DISTRIBUTION OF THE PROGRAM CONSTITUTES
* RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT.
*
* You may obtain a copy of the License at
*
* http://www.eclipse.org/legal/epl-v10.html
*
* 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.
*
* PlantUML can occasionally display sponsored or advertising messages. Those
* messages are usually generated on welcome or error images and never on
* functional diagrams.
* See https://plantuml.com/professional if you want to remove them
*
* Images (whatever their format : PNG, SVG, EPS...) generated by running PlantUML
* are owned by the author of their corresponding sources code (that is, their
* textual description in PlantUML language). Those images are not covered by
* this EPL license.
*
* The generated images can then be used without any reference to the EPL license.
* It is not even necessary to stipulate that they have been generated with PlantUML,
* although this will be appreciated by the PlantUML team.
*
* There is an exception : if the textual description in PlantUML language is also covered
* by any license, then the generated images are logically covered
* by the very same license.
*
* This is the IGY distribution (Install GraphViz by Yourself).
* You have to install GraphViz and to setup the GRAPHVIZ_DOT environment variable
* (see https://plantuml.com/graphviz-dot )
*
* Icons provided by OpenIconic : https://useiconic.com/open
* Archimate sprites provided by Archi : http://www.archimatetool.com
* Stdlib AWS provided by https://github.com/milo-minderbinder/AWS-PlantUML
* Stdlib Icons provided https://github.com/tupadr3/plantuml-icon-font-sprites
* ASCIIMathML (c) Peter Jipsen http://www.chapman.edu/~jipsen
* ASCIIMathML (c) David Lippman http://www.pierce.ctc.edu/dlippman
* CafeUndZopfli ported by Eugene Klyuchnikov https://github.com/eustas/CafeUndZopfli
* Brotli (c) by the Brotli Authors https://github.com/google/brotli
* Themes (c) by Brett Schwarz https://github.com/bschwarz/puml-themes
* Twemoji (c) by Twitter at https://twemoji.twitter.com/
*
*/
package net.sourceforge.plantuml.code.deflate;
/*
* Simple DEFLATE decompressor
* Copyright (c) Project Nayuki
*
* https://www.nayuki.io/page/simple-deflate-decompressor
* https://github.com/nayuki/Simple-DEFLATE-decompressor
*/
import java.io.IOException;
import java.util.Objects;
/**
* Stores a finite recent history of a byte stream. Useful as an implicit
* dictionary for Lempel-Ziv schemes. Mutable and not thread-safe.
*/
final class ByteHistory {
/*---- Fields ----*/
// Circular buffer of byte data.
private byte[] data;
// Index of next byte to write to, always in the range [0, data.length).
private int index;
/*---- Constructor ----*/
/**
* Constructs a byte history of the specified size, initialized to zeros.
*
* @param size the size, which must be positive
* @throws IllegalArgumentException if size is zero or negative
*/
public ByteHistory(int size) {
if (size < 1)
throw new IllegalArgumentException("Size must be positive");
data = new byte[size];
index = 0;
}
/*---- Methods ----*/
/**
* Appends the specified byte to this history. This overwrites the byte value at
* {@code size} positions ago.
*
* @param b the byte value to append
*/
public void append(int b) {
if (index < 0 || index >= data.length)
throw new IllegalStateException();
data[index] = (byte) b;
index = (index + 1) % data.length;
}
/**
* Copies {@code len} bytes starting at {@code dist} bytes ago to the specified
* output stream and also back into this buffer itself.
*
* Note that if the length exceeds the distance, then some of the output data
* will be a copy of data that was copied earlier in the process.
*
*
* @param dist the distance to go back, in the range [1, size]
* @param len the length to copy, which must be at least 0
* @param out the output stream to write to (not {@code null})
* @throws NullPointerException if the output stream is {@code null}
* @throws IllegalArgumentException if the length is negative, distance is not
* positive, or distance is greater than the
* buffer size
* @throws IOException if an I/O exception occurs
*/
public void copy(int dist, int len, OutputStreamProtected out) throws IOException {
Objects.requireNonNull(out);
if (len < 0 || dist < 1 || dist > data.length)
throw new IllegalArgumentException();
int readIndex = (index - dist + data.length) % data.length;
if (readIndex < 0 || readIndex >= data.length)
throw new IllegalStateException();
for (int i = 0; i < len; i++) {
byte b = data[readIndex];
readIndex = (readIndex + 1) % data.length;
out.write(b);
append(b);
}
}
}