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Diffstat (limited to 'framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/filters/HeadFilter.java')
| -rw-r--r-- | framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/filters/HeadFilter.java | 222 |
1 files changed, 0 insertions, 222 deletions
diff --git a/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/filters/HeadFilter.java b/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/filters/HeadFilter.java deleted file mode 100644 index 522fe57b..00000000 --- a/framework/src/ant/apache-ant-1.9.6/src/main/org/apache/tools/ant/filters/HeadFilter.java +++ /dev/null @@ -1,222 +0,0 @@ -/* - * 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. - * - */ -package org.apache.tools.ant.filters; - -import java.io.IOException; -import java.io.Reader; - -import org.apache.tools.ant.types.Parameter; -import org.apache.tools.ant.util.LineTokenizer; - -/** - * Reads the first <code>n</code> lines of a stream. - * (Default is first 10 lines.) - * <p> - * Example: - * <pre><headfilter lines="3"/></pre> - * Or: - * <pre><filterreader classname="org.apache.tools.ant.filters.HeadFilter"> - * <param name="lines" value="3"/> - * </filterreader></pre> - * - */ -public final class HeadFilter extends BaseParamFilterReader - implements ChainableReader { - /** Parameter name for the number of lines to be returned. */ - private static final String LINES_KEY = "lines"; - - /** Parameter name for the number of lines to be skipped. */ - private static final String SKIP_KEY = "skip"; - - /** Number of lines currently read in. */ - private long linesRead = 0; - - /** Default number of lines to show */ - private static final int DEFAULT_NUM_LINES = 10; - - /** Number of lines to be returned in the filtered stream. */ - private long lines = DEFAULT_NUM_LINES; - - /** Number of lines to be skipped. */ - private long skip = 0; - - /** A line tokenizer */ - private LineTokenizer lineTokenizer = null; - - /** the current line from the input stream */ - private String line = null; - /** the position in the current line */ - private int linePos = 0; - - /** Whether this filter is finished */ - private boolean eof; - - /** - * Constructor for "dummy" instances. - * - * @see BaseFilterReader#BaseFilterReader() - */ - public HeadFilter() { - super(); - } - - /** - * Creates a new filtered reader. - * - * @param in A Reader object providing the underlying stream. - * Must not be <code>null</code>. - */ - public HeadFilter(final Reader in) { - super(in); - lineTokenizer = new LineTokenizer(); - lineTokenizer.setIncludeDelims(true); - } - - /** - * Returns the next character in the filtered stream. If the desired - * number of lines have already been read, the resulting stream is - * effectively at an end. Otherwise, the next character from the - * underlying stream is read and returned. - * - * @return the next character in the resulting stream, or -1 - * if the end of the resulting stream has been reached - * - * @exception IOException if the underlying stream throws an IOException - * during reading - */ - public int read() throws IOException { - if (!getInitialized()) { - initialize(); - setInitialized(true); - } - - while (line == null || line.length() == 0) { - line = lineTokenizer.getToken(in); - if (line == null) { - return -1; - } - line = headFilter(line); - if (eof) { - return -1; - } - linePos = 0; - } - - int ch = line.charAt(linePos); - linePos++; - if (linePos == line.length()) { - line = null; - } - return ch; - } - - /** - * Sets the number of lines to be returned in the filtered stream. - * - * @param lines the number of lines to be returned in the filtered stream - */ - public void setLines(final long lines) { - this.lines = lines; - } - - /** - * Returns the number of lines to be returned in the filtered stream. - * - * @return the number of lines to be returned in the filtered stream - */ - private long getLines() { - return lines; - } - - /** - * Sets the number of lines to be skipped in the filtered stream. - * - * @param skip the number of lines to be skipped in the filtered stream - */ - public void setSkip(final long skip) { - this.skip = skip; - } - - /** - * Returns the number of lines to be skipped in the filtered stream. - * - * @return the number of lines to be skipped in the filtered stream - */ - private long getSkip() { - return skip; - } - - /** - * Creates a new HeadFilter using the passed in - * Reader for instantiation. - * - * @param rdr A Reader object providing the underlying stream. - * Must not be <code>null</code>. - * - * @return a new filter based on this configuration, but filtering - * the specified reader - */ - public Reader chain(final Reader rdr) { - HeadFilter newFilter = new HeadFilter(rdr); - newFilter.setLines(getLines()); - newFilter.setSkip(getSkip()); - newFilter.setInitialized(true); - return newFilter; - } - - /** - * Scans the parameters list for the "lines" parameter and uses - * it to set the number of lines to be returned in the filtered stream. - * also scan for skip parameter. - */ - private void initialize() { - Parameter[] params = getParameters(); - if (params != null) { - for (int i = 0; i < params.length; i++) { - if (LINES_KEY.equals(params[i].getName())) { - lines = Long.parseLong(params[i].getValue()); - continue; - } - if (SKIP_KEY.equals(params[i].getName())) { - skip = Long.parseLong(params[i].getValue()); - continue; - } - } - } - } - - /** - * implements a head filter on the input stream - */ - private String headFilter(String line) { - linesRead++; - if (skip > 0) { - if ((linesRead - 1) < skip) { - return null; - } - } - - if (lines > 0) { - if (linesRead > (lines + skip)) { - eof = true; - return null; - } - } - return line; - } -} |