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Diffstat (limited to 'velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/VelocityCharStream.java')
| -rw-r--r-- | velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/VelocityCharStream.java | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/VelocityCharStream.java b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/VelocityCharStream.java new file mode 100644 index 00000000..c5133749 --- /dev/null +++ b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/VelocityCharStream.java @@ -0,0 +1,526 @@ +package org.apache.velocity.runtime.parser; + +/* + * 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. + */ + +/** + * <p>An implementation of interface CharStream, where the stream is assumed to + * contain only ASCII characters (without unicode processing).</p> + * + * <p>NOTE : This class was originally an ASCII_CharStream autogenerated + * by Javacc. It was then modified via changing class name with appropriate + * fixes for CTORS, and mods to readChar().</p> + * + * <p>This is safe because we *always* use Reader with this class, and never a + * InputStream. This guarantees that we have a correct stream of 16-bit + * chars - all encoding transformations have been done elsewhere, so we + * believe that there is no risk in doing this. Time will tell :)</p> + * + */ +public final class VelocityCharStream +implements CharStream +{ + public static final boolean staticFlag = false; + int bufsize; + private int nextBufExpand; + int available; + int tokenBegin; + + public int bufpos = -1; + private int bufline[]; + private int bufcolumn[]; + + private int column = 0; + private int line = 1; + + private boolean prevCharIsCR = false; + private boolean prevCharIsLF = false; + + private java.io.Reader inputStream; + + private char[] buffer; + private int maxNextCharInd = 0; + private int inBuf = 0; + + /* CB - to properly handle EOF *inside* javacc lexer, + * we send a 'file separator' ascii char *just before* EOF + * (see https://en.wikipedia.org/wiki/Delimiter#ASCII_delimited_text) + */ + private boolean beforeEOF = false; + private static char END_OF_FILE = '\u001C'; + + private void ExpandBuff(boolean wrapAround) + { + char[] newbuffer = new char[bufsize + nextBufExpand]; + int newbufline[] = new int[bufsize + nextBufExpand]; + int newbufcolumn[] = new int[bufsize + nextBufExpand]; + + try + { + if (wrapAround) + { + System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin); + System.arraycopy(buffer, 0, newbuffer, + bufsize - tokenBegin, bufpos); + buffer = newbuffer; + + System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin); + System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos); + bufline = newbufline; + + System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin); + System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos); + bufcolumn = newbufcolumn; + + maxNextCharInd = (bufpos += (bufsize - tokenBegin)); + } + else + { + System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin); + buffer = newbuffer; + + System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin); + bufline = newbufline; + + System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin); + bufcolumn = newbufcolumn; + + maxNextCharInd = (bufpos -= tokenBegin); + } + } + catch (Throwable t) + { + throw new Error(t.getMessage()); + } + + + bufsize += nextBufExpand; + nextBufExpand = bufsize; + available = bufsize; + tokenBegin = 0; + } + + private void FillBuff() throws java.io.IOException + { + if (maxNextCharInd == available) + { + if (available == bufsize) + { + if (tokenBegin > nextBufExpand) + { + bufpos = maxNextCharInd = 0; + available = tokenBegin; + } + else if (tokenBegin < 0) + { + bufpos = maxNextCharInd = 0; + } + else + { + ExpandBuff(false); + } + } + else if (available > tokenBegin) + { + available = bufsize; + } + else if ((tokenBegin - available) < nextBufExpand) + { + ExpandBuff(true); + } + else + { + available = tokenBegin; + } + } + + int i; + try + { + if ((i = inputStream.read(buffer, maxNextCharInd, + available - maxNextCharInd)) == -1) + { + if (beforeEOF) + { + inputStream.close(); + throw new java.io.IOException(); + } + buffer[maxNextCharInd++] = END_OF_FILE; + beforeEOF = true; + } + else + { + maxNextCharInd += i; + } + } + catch(java.io.IOException e) + { + --bufpos; + backup(0); + if (tokenBegin == -1) + { + tokenBegin = bufpos; + } + throw e; + } + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#BeginToken() + */ + @Override + public final char BeginToken() throws java.io.IOException + { + tokenBegin = -1; + char c = readChar(); + tokenBegin = bufpos; + + return c; + } + + private void UpdateLineColumn(char c) + { + column++; + + if (prevCharIsLF) + { + prevCharIsLF = false; + line += (column = 1); + } + else if (prevCharIsCR) + { + prevCharIsCR = false; + if (c == '\n') + { + prevCharIsLF = true; + } + else + { + line += (column = 1); + } + } + + switch (c) + { + case '\r' : + prevCharIsCR = true; + break; + case '\n' : + prevCharIsLF = true; + break; + case '\t' : + column--; + column += (8 - (column & 07)); + break; + default : + break; + } + + bufline[bufpos] = line; + bufcolumn[bufpos] = column; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#readChar() + */ + @Override + public final char readChar() throws java.io.IOException + { + if (inBuf > 0) + { + --inBuf; + + /* + * was : return (char)((char)0xff & buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos]); + */ + return buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos]; + } + + if (++bufpos >= maxNextCharInd) + { + FillBuff(); + } + + /* + * was : char c = (char)((char)0xff & buffer[bufpos]); + */ + char c = buffer[bufpos]; + + UpdateLineColumn(c); + return (c); + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#getEndColumn() + */ + @Override + public final int getEndColumn() + { + return bufcolumn[bufpos]; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#getEndLine() + */ + @Override + public final int getEndLine() + { + return bufline[bufpos]; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#getBeginColumn() + */ + @Override + public final int getBeginColumn() + { + return bufcolumn[tokenBegin]; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#getBeginLine() + */ + @Override + public final int getBeginLine() + { + return bufline[tokenBegin]; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#backup(int) + */ + @Override + public final void backup(int amount) + { + + inBuf += amount; + if ((bufpos -= amount) < 0) + bufpos += bufsize; + } + + /** + * @param dstream + * @param startline + * @param startcolumn + * @param buffersize + */ + public VelocityCharStream(java.io.Reader dstream, int startline, + int startcolumn, int buffersize) + { + inputStream = dstream; + line = startline; + column = startcolumn - 1; + + available = bufsize = nextBufExpand = buffersize; + buffer = new char[buffersize]; + bufline = new int[buffersize]; + bufcolumn = new int[buffersize]; + } + + /** + * @param dstream + * @param startline + * @param startcolumn + */ + public VelocityCharStream(java.io.Reader dstream, int startline, + int startcolumn) + { + this(dstream, startline, startcolumn, 4096); + } + /** + * @param dstream + * @param startline + * @param startcolumn + * @param buffersize + */ + public void ReInit(java.io.Reader dstream, int startline, + int startcolumn, int buffersize) + { + inputStream = dstream; + line = startline; + column = startcolumn - 1; + + if (buffer == null || buffersize != buffer.length) + { + available = bufsize = nextBufExpand = buffersize; + buffer = new char[buffersize]; + bufline = new int[buffersize]; + bufcolumn = new int[buffersize]; + } + prevCharIsLF = prevCharIsCR = false; + tokenBegin = inBuf = maxNextCharInd = 0; + bufpos = -1; + beforeEOF = false; + } + + /** + * @param dstream + * @param startline + * @param startcolumn + */ + public void ReInit(java.io.Reader dstream, int startline, + int startcolumn) + { + ReInit(dstream, startline, startcolumn, 4096); + } + /** + * @param dstream + * @param startline + * @param startcolumn + * @param buffersize + */ + public VelocityCharStream(java.io.InputStream dstream, int startline, + int startcolumn, int buffersize) + { + this(new java.io.InputStreamReader(dstream), startline, startcolumn, buffersize); + } + + /** + * @param dstream + * @param startline + * @param startcolumn + */ + public VelocityCharStream(java.io.InputStream dstream, int startline, + int startcolumn) + { + this(dstream, startline, startcolumn, 4096); + } + + /** + * @param dstream + * @param startline + * @param startcolumn + * @param buffersize + */ + public void ReInit(java.io.InputStream dstream, int startline, + int startcolumn, int buffersize) + { + ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, buffersize); + } + /** + * @param dstream + * @param startline + * @param startcolumn + */ + public void ReInit(java.io.InputStream dstream, int startline, + int startcolumn) + { + ReInit(dstream, startline, startcolumn, 4096); + } + /** + * @see org.apache.velocity.runtime.parser.CharStream#GetImage() + */ + @Override + public final String GetImage() + { + if (bufpos >= tokenBegin) + { + return new String(buffer, tokenBegin, bufpos - tokenBegin + 1); + } + else + { + return new String(buffer, tokenBegin, bufsize - tokenBegin) + + new String(buffer, 0, bufpos + 1); + } + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#GetSuffix(int) + */ + @Override + public final char[] GetSuffix(int len) + { + char[] ret = new char[len]; + + if ((bufpos + 1) >= len) + { + System.arraycopy(buffer, bufpos - len + 1, ret, 0, len); + } + else + { + System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0, + len - bufpos - 1); + System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1); + } + + return ret; + } + + /** + * @see org.apache.velocity.runtime.parser.CharStream#Done() + */ + @Override + public void Done() + { + buffer = null; + bufline = null; + bufcolumn = null; + } + + /** + * Method to adjust line and column numbers for the start of a token.<BR> + * @param newLine + * @param newCol + */ + public void adjustBeginLineColumn(int newLine, int newCol) + { + int start = tokenBegin; + int len; + + if (bufpos >= tokenBegin) + { + len = bufpos - tokenBegin + inBuf + 1; + } + else + { + len = bufsize - tokenBegin + bufpos + 1 + inBuf; + } + + int i = 0, j = 0, k = 0; + int nextColDiff = 0, columnDiff = 0; + + while (i < len && + bufline[j = start % bufsize] == bufline[k = ++start % bufsize]) + { + bufline[j] = newLine; + nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j]; + bufcolumn[j] = newCol + columnDiff; + columnDiff = nextColDiff; + i++; + } + + if (i < len) + { + bufline[j] = newLine++; + bufcolumn[j] = newCol + columnDiff; + + while (i++ < len) + { + if (bufline[j = start % bufsize] != bufline[++start % bufsize]) + bufline[j] = newLine++; + else + bufline[j] = newLine; + } + } + + line = bufline[j]; + column = bufcolumn[j]; + } + +} |