org.apache.hadoop.fs.shell.find.Print Maven / Gradle / Ivy
/**
* 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.hadoop.fs.shell.find;
import java.io.IOException;
import org.apache.hadoop.fs.shell.PathData;
/**
* Implements the -print expression for the
* {@link org.apache.hadoop.fs.shell.find.Find} command.
*/
final class Print extends BaseExpression {
/** Registers this expression with the specified factory. */
public static void registerExpression(ExpressionFactory factory)
throws IOException {
factory.addClass(Print.class, "-print");
factory.addClass(Print0.class, "-print0");
}
private static final String[] USAGE = { "-print", "-print0" };
private static final String[] HELP = {
"Always evaluates to true. Causes the current pathname to be",
"written to standard output followed by a newline. If the -print0",
"expression is used then an ASCII NULL character is appended rather",
"than a newline." };
private final String suffix;
public Print() {
this("\n");
}
/**
* Construct a Print {@link Expression} with the specified suffix.
*/
private Print(String suffix) {
super();
setUsage(USAGE);
setHelp(HELP);
this.suffix = suffix;
}
@Override
public Result apply(PathData item, int depth) throws IOException {
getOptions().getOut().print(item.toString() + suffix);
return Result.PASS;
}
@Override
public boolean isAction() {
return true;
}
/** Implements the -print0 expression. */
final static class Print0 extends FilterExpression {
public Print0() {
super(new Print("\0"));
}
}
}