/*
* 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.pig.impl.io;
import java.io.IOException;
import org.apache.pig.FuncSpec;
import org.apache.pig.Slicer;
import org.apache.pig.ExecType;
import org.apache.pig.backend.datastorage.DataStorage;
import org.apache.pig.backend.executionengine.PigSlicer;
import org.apache.pig.impl.PigContext;
/**
* Creates a Slicer using its funcSpec in its construction and checks that it's
* valid.
*/
public class ValidatingInputFileSpec extends FileSpec {
// Don't send the instantiated slicer over the wire.
private transient Slicer slicer;
private static final long serialVersionUID = 1L;
public ValidatingInputFileSpec(FileSpec fileSpec, DataStorage store)
throws IOException {
super(fileSpec.getFileName(), fileSpec.getFuncSpec());
validate(store);
}
/**
* If the <code>ExecType</code> of <code>context</code> is LOCAL,
* validation is not performed.
*/
public ValidatingInputFileSpec(String fileName, String funcSpec,
PigContext context) throws IOException {
super(fileName, new FuncSpec(funcSpec));
validate(context.getFs());
}
private void validate(DataStorage store) throws IOException {
getSlicer().validate(store, getFileName());
}
/**
* Returns the Slicer created by this spec's funcSpec.
*/
public Slicer getSlicer() {
if (slicer == null) {
Object loader = PigContext.instantiateFuncFromSpec(getFuncSpec());
if (loader instanceof Slicer) {
slicer = (Slicer) loader;
} else {
slicer = new PigSlicer(getFuncSpec());
}
}
return slicer;
}
}