/*
* Cloud9: A MapReduce Library for Hadoop
*
* Licensed 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 edu.umd.cloud9.webgraph.data;
import java.io.IOException;
import java.text.DecimalFormat;
import java.util.Arrays;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.SequenceFile;
import edu.umd.cloud9.collection.DocnoMapping;
import edu.umd.cloud9.collection.DocumentForwardIndex;
import edu.umd.cloud9.io.array.ArrayListWritable;
public class IndexableAnchorTextForwardIndex implements DocumentForwardIndex<IndexableAnchorText> {
private static final IndexableAnchorText indexableAnchorText = new IndexableAnchorText();
private static final DecimalFormat df = new DecimalFormat("00000");
private Configuration conf;
private FileSystem fs;
private int[] docnos;
private int[] offsets;
private short[] filenos;
private String collectionPath;
private DocnoMapping docnoMapping;
public IndexableAnchorTextForwardIndex(DocnoMapping docnoMapping) {
this.docnoMapping = docnoMapping;
}
@Override
public void loadIndex(Path index, Path mapping, FileSystem fs) throws IOException {
docnoMapping.loadMapping(mapping, fs);
FSDataInputStream in = fs.open(index);
// class name; throw away
in.readUTF();
collectionPath = in.readUTF();
int blocks = in.readInt();
docnos = new int[blocks];
offsets = new int[blocks];
filenos = new short[blocks];
for (int i = 0; i < blocks; i++) {
docnos[i] = in.readInt();
offsets[i] = in.readInt();
filenos[i] = in.readShort();
}
in.close();
}
public String getCollectionPath() {
return collectionPath;
}
public IndexableAnchorText getDocument(int docno) {
int idx = Arrays.binarySearch(docnos, docno);
if (idx < 0)
idx = -idx - 2;
DecimalFormat df = new DecimalFormat("00000");
String file = collectionPath + "/part-" + df.format(filenos[idx]);
try {
SequenceFile.Reader reader = new SequenceFile.Reader(fs, new Path(file), conf);
IntWritable key = new IntWritable();
ArrayListWritable<AnchorText> value = new ArrayListWritable<AnchorText>();
reader.seek(offsets[idx]);
while (reader.next(key)) {
if (key.get() == docno)
break;
}
reader.getCurrentValue(value);
reader.close();
indexableAnchorText.createHTML(value);
return indexableAnchorText;
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
public IndexableAnchorText getDocument(String docid) {
return getDocument(docnoMapping.getDocno(docid));
}
public int getDocno(String docid) {
return docnoMapping.getDocno(docid);
}
public String getDocid(int docno) {
return docnoMapping.getDocid(docno);
}
public int getFirstDocno() {
return docnos[0];
}
private int mLastDocno = -1;
public int getLastDocno() {
if (mLastDocno != -1)
return mLastDocno;
// find the last entry, and then see all the way to the end of the
// collection
int idx = docnos.length - 1;
String file = collectionPath + "/part-" + df.format(filenos[idx]);
try {
SequenceFile.Reader reader = new SequenceFile.Reader(fs, new Path(file), conf);
IntWritable key = new IntWritable();
reader.seek(offsets[idx]);
while (reader.next(key))
;
mLastDocno = key.get();
} catch (IOException e) {
e.printStackTrace();
}
return mLastDocno;
}
public String getContentType() {
return "text/html";
}
public String getDisplayContentType() {
return "text/html";
}
}