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Posted to commits@crunch.apache.org by gr...@apache.org on 2012/10/05 14:02:52 UTC

git commit: Add javadoc to MRPipeline constructors

Updated Branches:
  refs/heads/master ef10e80bc -> ed7481d9c


Add javadoc to MRPipeline constructors


Project: http://git-wip-us.apache.org/repos/asf/incubator-crunch/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-crunch/commit/ed7481d9
Tree: http://git-wip-us.apache.org/repos/asf/incubator-crunch/tree/ed7481d9
Diff: http://git-wip-us.apache.org/repos/asf/incubator-crunch/diff/ed7481d9

Branch: refs/heads/master
Commit: ed7481d9c88fc9968efa24a18d9b63ce25f0f9d0
Parents: ef10e80
Author: Gabriel Reid <gr...@apache.org>
Authored: Fri Oct 5 14:02:22 2012 +0200
Committer: Gabriel Reid <gr...@apache.org>
Committed: Fri Oct 5 14:02:22 2012 +0200

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 .../java/org/apache/crunch/impl/mr/MRPipeline.java |   58 ++++++++++----
 1 files changed, 41 insertions(+), 17 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-crunch/blob/ed7481d9/crunch/src/main/java/org/apache/crunch/impl/mr/MRPipeline.java
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diff --git a/crunch/src/main/java/org/apache/crunch/impl/mr/MRPipeline.java b/crunch/src/main/java/org/apache/crunch/impl/mr/MRPipeline.java
index f32783a..043f7b1 100644
--- a/crunch/src/main/java/org/apache/crunch/impl/mr/MRPipeline.java
+++ b/crunch/src/main/java/org/apache/crunch/impl/mr/MRPipeline.java
@@ -58,6 +58,9 @@ import org.apache.log4j.Logger;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 
+/**
+ * Pipeline implementation that is executed within Hadoop MapReduce.
+ */
 public class MRPipeline implements Pipeline {
 
   private static final Log LOG = LogFactory.getLog(MRPipeline.class);
@@ -74,18 +77,43 @@ public class MRPipeline implements Pipeline {
 
   private Configuration conf;
 
+  /**
+   * Instantiate with a default Configuration and name.
+   * 
+   * @param jarClass Class containing the main driver method for running the pipeline
+   */
   public MRPipeline(Class<?> jarClass) {
     this(jarClass, new Configuration());
   }
 
+  /**
+   * Instantiate with a custom pipeline name. The name will be displayed in the Hadoop JobTracker.
+   * 
+   * @param jarClass Class containing the main driver method for running the pipeline
+   * @param name Display name of the pipeline
+   */
   public MRPipeline(Class<?> jarClass, String name) {
     this(jarClass, name, new Configuration());
   }
 
+  /**
+   * Instantiate with a custom configuration and default naming.
+   * 
+   * @param jarClass Class containing the main driver method for running the pipeline
+   * @param conf Configuration to be used within all MapReduce jobs run in the pipeline
+   */
   public MRPipeline(Class<?> jarClass, Configuration conf) {
     this(jarClass, jarClass.getName(), conf);
   }
 
+  /**
+   * Instantiate with a custom name and configuration. The name will be displayed in the Hadoop
+   * JobTracker.
+   * 
+   * @param jarClass Class containing the main driver method for running the pipeline
+   * @param name Display name of the pipeline
+   * @param conf Configuration to be used within all MapReduce jobs run in the pipeline
+   */
   public MRPipeline(Class<?> jarClass, String name, Configuration conf) {
     this.jarClass = jarClass;
     this.name = name;
@@ -165,8 +193,8 @@ public class MRPipeline implements Pipeline {
     if (pcollection instanceof PGroupedTableImpl) {
       pcollection = ((PGroupedTableImpl<?, ?>) pcollection).ungroup();
     } else if (pcollection instanceof UnionCollection || pcollection instanceof UnionTable) {
-      pcollection = pcollection.parallelDo("UnionCollectionWrapper", (MapFn) IdentityFn.<Object> getInstance(),
-          pcollection.getPType());
+      pcollection = pcollection.parallelDo("UnionCollectionWrapper",
+          (MapFn) IdentityFn.<Object> getInstance(), pcollection.getPType());
     }
     addOutput((PCollectionImpl<?>) pcollection, target);
   }
@@ -192,17 +220,14 @@ public class MRPipeline implements Pipeline {
   }
 
   /**
-   * Retrieve a ReadableSourceTarget that provides access to the contents of a
-   * {@link PCollection}. This is primarily intended as a helper method to
-   * {@link #materialize(PCollection)}. The underlying data of the
-   * ReadableSourceTarget may not be actually present until the pipeline is run.
+   * Retrieve a ReadableSourceTarget that provides access to the contents of a {@link PCollection}.
+   * This is primarily intended as a helper method to {@link #materialize(PCollection)}. The
+   * underlying data of the ReadableSourceTarget may not be actually present until the pipeline is
+   * run.
    * 
-   * @param pcollection
-   *          The collection for which the ReadableSourceTarget is to be
-   *          retrieved
+   * @param pcollection The collection for which the ReadableSourceTarget is to be retrieved
    * @return The ReadableSourceTarget
-   * @throws IllegalArgumentException
-   *           If no ReadableSourceTarget can be retrieved for the given
+   * @throws IllegalArgumentException If no ReadableSourceTarget can be retrieved for the given
    *           PCollection
    */
   public <T> ReadableSourceTarget<T> getMaterializeSourceTarget(PCollection<T> pcollection) {
@@ -237,11 +262,10 @@ public class MRPipeline implements Pipeline {
   }
 
   /**
-   * Safely cast a PCollection into a PCollectionImpl, including handling the
-   * case of UnionCollections.
+   * Safely cast a PCollection into a PCollectionImpl, including handling the case of
+   * UnionCollections.
    * 
-   * @param pcollection
-   *          The PCollection to be cast/transformed
+   * @param pcollection The PCollection to be cast/transformed
    * @return The PCollectionImpl representation
    */
   private <T> PCollectionImpl<T> toPcollectionImpl(PCollection<T> pcollection) {
@@ -282,8 +306,8 @@ public class MRPipeline implements Pipeline {
   @Override
   public <T> void writeTextFile(PCollection<T> pcollection, String pathName) {
     // Ensure that this is a writable pcollection instance.
-    pcollection = pcollection.parallelDo("asText", IdentityFn.<T> getInstance(),
-        WritableTypeFamily.getInstance().as(pcollection.getPType()));
+    pcollection = pcollection.parallelDo("asText", IdentityFn.<T> getInstance(), WritableTypeFamily
+        .getInstance().as(pcollection.getPType()));
     write(pcollection, At.textFile(pathName));
   }