Author: rvesse
Date: Wed Jul 9 10:16:15 2014
New Revision: 1609075
URL: http://svn.apache.org/r1609075
Log:
Add various additional useful utility mapper and reducer classes
Added:
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyMapper.java
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyReducer.java
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueMapper.java
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueReducer.java
Added:
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyMapper.java
URL:
http://svn.apache.org/viewvc/jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyMapper.java?rev=1609075&view=auto
==============================================================================
---
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyMapper.java
(added)
+++
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyMapper.java
Wed Jul 9 10:16:15 2014
@@ -0,0 +1,55 @@
+/*
+ * 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.jena.hadoop.rdf.mapreduce;
+
+import java.io.IOException;
+
+import org.apache.hadoop.io.NullWritable;
+import org.apache.hadoop.mapreduce.Mapper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A mapper which discards the value, moves the key to the value position and
uses a null key
+ *
+ *
+ * @param <TKey> Key type
+ * @param <TValue> Value type
+ */
+public class NullPlusKeyMapper<TKey, TValue> extends Mapper<TKey, TValue,
NullWritable, TKey> {
+ private static final Logger LOG =
LoggerFactory.getLogger(NullPlusKeyMapper.class);
+
+ private boolean tracing = false;
+
+ @Override
+ protected void setup(Context context) throws IOException,
InterruptedException {
+ super.setup(context);
+ this.tracing = LOG.isTraceEnabled();
+ }
+
+ @Override
+ protected void map(TKey key, TValue value, Context context) throws
IOException,
+ InterruptedException {
+ if (this.tracing) {
+ LOG.trace("Key = {}", key);
+ }
+ context.write(NullWritable.get(), key);
+ }
+
+}
Added:
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyReducer.java
URL:
http://svn.apache.org/viewvc/jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyReducer.java?rev=1609075&view=auto
==============================================================================
---
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyReducer.java
(added)
+++
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusKeyReducer.java
Wed Jul 9 10:16:15 2014
@@ -0,0 +1,40 @@
+/*
+ * 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.jena.hadoop.rdf.mapreduce;
+
+import java.io.IOException;
+
+import org.apache.hadoop.io.NullWritable;
+import org.apache.hadoop.mapreduce.Reducer;
+
+/**
+ * A reducer that outputs a single pair consists of a null as the key and the
key as the value
+ * @author rvesse
+ *
+ * @param <TKey> Key
+ * @param <TValue> Value
+ */
+public class NullPlusKeyReducer<TKey, TValue> extends Reducer<TKey, TValue,
NullWritable, TKey> {
+
+ @Override
+ protected void reduce(TKey key, Iterable<TValue> values, Context context)
+ throws IOException, InterruptedException {
+ context.write(NullWritable.get(), key);
+ }
+}
Added:
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueMapper.java
URL:
http://svn.apache.org/viewvc/jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueMapper.java?rev=1609075&view=auto
==============================================================================
---
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueMapper.java
(added)
+++
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueMapper.java
Wed Jul 9 10:16:15 2014
@@ -0,0 +1,55 @@
+/*
+ * 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.jena.hadoop.rdf.mapreduce;
+
+import java.io.IOException;
+
+import org.apache.hadoop.io.NullWritable;
+import org.apache.hadoop.mapreduce.Mapper;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A mapper which discards the key replacing it with a null leaving the value
as is
+ *
+ *
+ * @param <TKey> Key type
+ * @param <TValue> Value type
+ */
+public class NullPlusValueMapper<TKey, TValue> extends Mapper<TKey, TValue,
NullWritable, TValue> {
+ private static final Logger LOG =
LoggerFactory.getLogger(NullPlusValueMapper.class);
+
+ private boolean tracing = false;
+
+ @Override
+ protected void setup(Context context) throws IOException,
InterruptedException {
+ super.setup(context);
+ this.tracing = LOG.isTraceEnabled();
+ }
+
+ @Override
+ protected void map(TKey key, TValue value, Context context) throws
IOException,
+ InterruptedException {
+ if (this.tracing) {
+ LOG.trace("Value = {}", value);
+ }
+ context.write(NullWritable.get(), value);
+ }
+
+}
Added:
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueReducer.java
URL:
http://svn.apache.org/viewvc/jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueReducer.java?rev=1609075&view=auto
==============================================================================
---
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueReducer.java
(added)
+++
jena/Experimental/hadoop-rdf/hadoop-rdf-mapreduce/src/main/java/org/apache/jena/hadoop/rdf/mapreduce/NullPlusValueReducer.java
Wed Jul 9 10:16:15 2014
@@ -0,0 +1,45 @@
+/*
+ * 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.jena.hadoop.rdf.mapreduce;
+
+import java.io.IOException;
+import java.util.Iterator;
+
+import org.apache.hadoop.io.NullWritable;
+import org.apache.hadoop.mapreduce.Reducer;
+
+/**
+ * A reducer that outputs a pair for each value consisting of a null key and
the value
+ * @author rvesse
+ *
+ * @param <TKey> Key
+ * @param <TValue> Value
+ */
+public class NullPlusValueReducer<TKey, TValue> extends Reducer<TKey, TValue,
NullWritable, TValue> {
+
+ @Override
+ protected void reduce(TKey key, Iterable<TValue> values, Context context)
+ throws IOException, InterruptedException {
+ Iterator<TValue> iter = values.iterator();
+ while (iter.hasNext()) {
+ TValue value = iter.next();
+ context.write(NullWritable.get(), value);
+ }
+ }
+}
