| /* |
| * 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 |
| * |
| * https://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. |
| * |
| */ |
| package org.apache.tools.ant.filters; |
| |
| import java.io.FilterReader; |
| import java.io.IOException; |
| import java.io.Reader; |
| import java.io.StringReader; |
| |
| import org.apache.tools.ant.Project; |
| import org.apache.tools.ant.util.FileUtils; |
| |
| /** |
| * Base class for core filter readers. |
| * |
| */ |
| public abstract class BaseFilterReader extends FilterReader { |
| /** Buffer size used when reading */ |
| private static final int BUFFER_SIZE = 8192; |
| |
| /** Have the parameters passed been interpreted? */ |
| private boolean initialized = false; |
| |
| /** The Ant project this filter is part of. */ |
| private Project project = null; |
| |
| /** |
| * Constructor used by Ant's introspection mechanism. |
| * The original filter reader is only used for chaining |
| * purposes, never for filtering purposes (and indeed |
| * it would be useless for filtering purposes, as it has |
| * no real data to filter). ChainedReaderHelper uses |
| * this placeholder instance to create a chain of real filters. |
| */ |
| public BaseFilterReader() { |
| super(new StringReader("")); |
| FileUtils.close(this); |
| } |
| |
| /** |
| * Creates a new filtered reader. |
| * |
| * @param in A Reader object providing the underlying stream. |
| * Must not be <code>null</code>. |
| * |
| */ |
| public BaseFilterReader(final Reader in) { |
| super(in); |
| } |
| |
| /** |
| * Reads characters into a portion of an array. This method will block |
| * until some input is available, an I/O error occurs, or the end of the |
| * stream is reached. |
| * |
| * @param cbuf Destination buffer to write characters to. |
| * Must not be <code>null</code>. |
| * @param off Offset at which to start storing characters. |
| * @param len Maximum number of characters to read. |
| * |
| * @return the number of characters read, or -1 if the end of the |
| * stream has been reached |
| * |
| * @exception IOException If an I/O error occurs |
| */ |
| public final int read(final char[] cbuf, final int off, |
| final int len) throws IOException { |
| for (int i = 0; i < len; i++) { |
| final int ch = read(); |
| if (ch == -1) { |
| if (i == 0) { |
| return -1; |
| } else { |
| return i; |
| } |
| } |
| cbuf[off + i] = (char) ch; |
| } |
| return len; |
| } |
| |
| /** |
| * Skips characters. This method will block until some characters are |
| * available, an I/O error occurs, or the end of the stream is reached. |
| * |
| * @param n The number of characters to skip |
| * |
| * @return the number of characters actually skipped |
| * |
| * @exception IllegalArgumentException If <code>n</code> is negative. |
| * @exception IOException If an I/O error occurs |
| */ |
| public final long skip(final long n) |
| throws IOException, IllegalArgumentException { |
| if (n < 0L) { |
| throw new IllegalArgumentException("skip value is negative"); |
| } |
| |
| for (long i = 0; i < n; i++) { |
| if (read() == -1) { |
| return i; |
| } |
| } |
| return n; |
| } |
| |
| /** |
| * Sets the initialized status. |
| * |
| * @param initialized Whether or not the filter is initialized. |
| */ |
| protected final void setInitialized(final boolean initialized) { |
| this.initialized = initialized; |
| } |
| |
| /** |
| * Returns the initialized status. |
| * |
| * @return whether or not the filter is initialized |
| */ |
| protected final boolean getInitialized() { |
| return initialized; |
| } |
| |
| /** |
| * Sets the project to work with. |
| * |
| * @param project The project this filter is part of. |
| * Should not be <code>null</code>. |
| */ |
| public final void setProject(final Project project) { |
| this.project = project; |
| } |
| |
| /** |
| * Returns the project this filter is part of. |
| * |
| * @return the project this filter is part of |
| */ |
| protected final Project getProject() { |
| return project; |
| } |
| |
| /** |
| * Reads a line of text ending with '\n' (or until the end of the stream). |
| * The returned String retains the '\n'. |
| * |
| * @return the line read, or <code>null</code> if the end of the stream |
| * has already been reached |
| * |
| * @exception IOException if the underlying reader throws one during |
| * reading |
| */ |
| protected final String readLine() throws IOException { |
| int ch = in.read(); |
| |
| if (ch == -1) { |
| return null; |
| } |
| |
| final StringBuilder line = new StringBuilder(); |
| |
| while (ch != -1) { |
| line.append((char) ch); |
| if (ch == '\n') { |
| break; |
| } |
| ch = in.read(); |
| } |
| return line.toString(); |
| } |
| |
| /** |
| * Reads to the end of the stream, returning the contents as a String. |
| * |
| * @return the remaining contents of the reader, as a String |
| * |
| * @exception IOException if the underlying reader throws one during |
| * reading |
| */ |
| protected final String readFully() throws IOException { |
| return FileUtils.readFully(in, BUFFER_SIZE); |
| } |
| } |