HADOOP-1746 Clean up findbugs warnings

git-svn-id: https://svn.apache.org/repos/asf/lucene/hadoop/trunk@568776 13f79535-47bb-0310-9956-ffa450edef68

src/contrib/hbase/CHANGES.txt

@@ -19,6 +19,7 @@ Trunk (unreleased changes)
 
   IMPROVEMENTS
     HADOOP-1737 Make HColumnDescriptor data publically members settable
+    HADOOP-1746 Clean up findbugs warnings
 
 
 Below are the list of changes before 2007-08-18

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HAbstractScanner.java

@@ -185,9 +185,6 @@ public abstract class HAbstractScanner implements HInternalScannerInterface {
   /** Mechanism used by concrete implementation to shut down a particular scanner */
   abstract void closeSubScanner(int i);
   
-  /** Mechanism used to shut down the whole scan */
-  public abstract void close();
-
   /** {@inheritDoc} */
   public boolean isWildcardScanner() {
     return this.wildcardMatch;

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HColumnDescriptor.java

@@ -37,7 +37,7 @@ public class HColumnDescriptor implements WritableComparable {
   // For future backward compatibility
   private static final byte COLUMN_DESCRIPTOR_VERSION = (byte)1;
   
-  // Legal family names can only contain 'word characters' and end in a colon.
+  /** Legal family names can only contain 'word characters' and end in a colon. */
   public static final Pattern LEGAL_FAMILY_NAME = Pattern.compile("\\w+:");
 
   /** 

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HLog.java

@@ -83,7 +83,7 @@ public class HLog implements HConstants {
   long filenum = 0;
   AtomicInteger numEntries = new AtomicInteger(0);
 
-  Integer rollLock = Integer.valueOf(0);
+  Integer rollLock = new Integer(0);
 
   /**
    * Split up a bunch of log files, that are no longer being written to,

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HLogEdit.java

@@ -34,7 +34,7 @@ public class HLogEdit implements Writable {
   private Text column = new Text();
   private byte [] val;
   private long timestamp;
-  private final int MAX_VALUE_LEN = 128;
+  private static final int MAX_VALUE_LEN = 128;
 
   /**
    * Default constructor used by Writable

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HMaster.java

@@ -67,6 +67,7 @@ import org.apache.hadoop.hbase.io.BatchUpdate;
 public class HMaster implements HConstants, HMasterInterface, 
 HMasterRegionInterface, Runnable {
 
+  /** {@inheritDoc} */
   public long getProtocolVersion(String protocol,
       @SuppressWarnings("unused") long clientVersion) throws IOException {
 
@@ -322,7 +323,7 @@ HMasterRegionInterface, Runnable {
           LOG.warn("Deletion of " + parent.getRegionName() + " failed");
         }
         
-        BatchUpdate b = new BatchUpdate();
+        BatchUpdate b = new BatchUpdate(rand.nextLong());
         long lockid = b.startUpdate(parent.getRegionName());
         b.delete(lockid, COL_REGIONINFO);
         b.delete(lockid, COL_SERVER);
@@ -388,7 +389,7 @@ HMasterRegionInterface, Runnable {
             +" no longer has references to " + parent.toString());
       }
       
-      BatchUpdate b = new BatchUpdate();
+      BatchUpdate b = new BatchUpdate(rand.nextLong());
       long lockid = b.startUpdate(parent);
       b.delete(lockid, splitColumn);
       srvr.batchUpdate(metaRegionName, System.currentTimeMillis(), b);
@@ -542,7 +543,7 @@ HMasterRegionInterface, Runnable {
 
   private RootScanner rootScanner;
   private Thread rootScannerThread;
-  Integer rootScannerLock = Integer.valueOf(0);
+  Integer rootScannerLock = new Integer(0);
 
   @SuppressWarnings("unchecked")
   static class MetaRegion implements Comparable {
@@ -731,7 +732,7 @@ HMasterRegionInterface, Runnable {
 
   MetaScanner metaScanner;
   private Thread metaScannerThread;
-  Integer metaScannerLock = Integer.valueOf(0);
+  Integer metaScannerLock = new Integer(0);
 
   /**
    * The 'unassignedRegions' table maps from a region name to a HRegionInfo 
@@ -938,6 +939,7 @@ HMasterRegionInterface, Runnable {
     Thread.currentThread().setName("HMaster");
     try { 
       // Start things up
+      this.serverLeases.start();
       this.rootScannerThread.start();
       this.metaScannerThread.start();
 
@@ -1824,7 +1826,7 @@ HMasterRegionInterface, Runnable {
       // Remove server from root/meta entries
       
       for (ToDoEntry e: toDoList) {
-        BatchUpdate b = new BatchUpdate();
+        BatchUpdate b = new BatchUpdate(rand.nextLong());
         long lockid = b.startUpdate(e.row);
       
         if (e.deleteRegion) {
@@ -2094,7 +2096,7 @@ HMasterRegionInterface, Runnable {
         }
 
         try {
-          BatchUpdate b = new BatchUpdate();
+          BatchUpdate b = new BatchUpdate(rand.nextLong());
           long lockid = b.startUpdate(regionInfo.regionName);
 
           if (deleteRegion) {
@@ -2239,7 +2241,7 @@ HMasterRegionInterface, Runnable {
           serverAddress.toString());
 
         try {
-          BatchUpdate b = new BatchUpdate();
+          BatchUpdate b = new BatchUpdate(rand.nextLong());
           long lockid = b.startUpdate(region.getRegionName());
           b.put(lockid, COL_SERVER,
             Writables.stringToBytes(serverAddress.toString()));
@@ -2404,7 +2406,7 @@ HMasterRegionInterface, Runnable {
           
       HRegionInfo info = region.getRegionInfo();
       Text regionName = region.getRegionName();
-      BatchUpdate b = new BatchUpdate();
+      BatchUpdate b = new BatchUpdate(rand.nextLong());
       long lockid = b.startUpdate(regionName);
       b.put(lockid, COL_REGIONINFO, Writables.getBytes(info));
       server.batchUpdate(metaRegionName, System.currentTimeMillis(), b);
@@ -2689,7 +2691,7 @@ HMasterRegionInterface, Runnable {
           LOG.debug("updating columns in row: " + i.regionName);
         }
 
-        BatchUpdate b = new BatchUpdate();
+        BatchUpdate b = new BatchUpdate(rand.nextLong());
         lockid = b.startUpdate(i.regionName);
         updateRegionInfo(b, i);
         b.delete(lockid, COL_SERVER);
@@ -2846,7 +2848,7 @@ HMasterRegionInterface, Runnable {
     protected void updateRegionInfo(HRegionInterface server, Text regionName,
         HRegionInfo i) throws IOException {
 
-      BatchUpdate b = new BatchUpdate();
+      BatchUpdate b = new BatchUpdate(rand.nextLong());
       long lockid = b.startUpdate(i.regionName);
       b.put(lockid, COL_REGIONINFO, Writables.getBytes(i));
       

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HMemcache.java

@@ -380,7 +380,6 @@ public class HMemcache {
     }
 
     /** Shut down map iterators, and release the lock */
-    @Override
     public void close() {
       if(! scannerClosed) {
         try {

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HRegion.java

@@ -74,7 +74,6 @@ import org.apache.hadoop.util.StringUtils;
 public class HRegion implements HConstants {
   static String SPLITDIR = "splits";
   static String MERGEDIR = "merges";
-  static String TMPREGION_PREFIX = "tmpregion_";
   static final Random rand = new Random();
   static final Log LOG = LogFactory.getLog(HRegion.class);
   final AtomicBoolean closed = new AtomicBoolean(false);
@@ -991,7 +990,7 @@ public class HRegion implements HConstants {
         storelist.add(stores.get(family));
       }
       return new HScanner(cols, firstRow, timestamp, memcache,
-        storelist.toArray(new HStore [] {}), filter);
+        storelist.toArray(new HStore [storelist.size()]), filter);
     } finally {
       lock.releaseReadLock();
     }

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HRegionServer.java

@@ -577,6 +577,7 @@ public class HRegionServer implements HConstants, HRegionInterface, Runnable {
     logRollerThread.start();
     leases = new Leases(conf.getLong("hbase.regionserver.lease.period", 
         3 * 60 * 1000), threadWakeFrequency);
+    leases.start();
     
     // Server
     
@@ -1310,7 +1311,7 @@ public class HRegionServer implements HConstants, HRegionInterface, Runnable {
       s = scanners.remove(scannerName);
     }
     if(s == null) {
-      throw new UnknownScannerException(scannerName.toString());
+      throw new UnknownScannerException(scannerName);
     }
     s.close();
     leases.cancelLease(scannerId, scannerId);

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HRegiondirReader.java

@@ -141,14 +141,14 @@ class HRegiondirReader {
       Text family = new Text(d.getName() + ":");
       families.add(family);
     }
-    return families.toArray(new Text [] {});
+    return families.toArray(new Text [families.size()]);
   }
   
   List <HRegionInfo> getRegions() {
     return this.infos;
   }
   
-  HRegionInfo getRegionInfo(final String tableName) {
+  HRegionInfo getRegionInfo(final Text tableName) {
     HRegionInfo result = null;
     for(HRegionInfo i: getRegions()) {
       if(i.tableDesc.getName().equals(tableName)) {
@@ -163,14 +163,15 @@ class HRegiondirReader {
     return result;
   }
   
-  private void dump(final String tableName) throws IOException {
+  private void dump(final Text tableName) throws IOException {
     dump(getRegionInfo(tableName));
   }
   
   private void dump(final HRegionInfo info) throws IOException {
     HRegion r = new HRegion(this.parentdir, null,
         FileSystem.get(this.conf), conf, info, null);
-    Text [] families = info.tableDesc.families().keySet().toArray(new Text [] {});
+    Text [] families = info.tableDesc.families().keySet().toArray(
+        new Text [info.tableDesc.families.size()]);
     HInternalScannerInterface scanner =
       r.getScanner(families, new Text(), System.currentTimeMillis(), null);
     
@@ -224,7 +225,7 @@ class HRegiondirReader {
       }
     } else {
       for (int i = 1; i < args.length; i++) {
-        reader.dump(args[i]);
+        reader.dump(new Text(args[i]));
       }
     }
   }

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HStore.java

@@ -742,7 +742,7 @@ class HStore implements HConstants {
   }
 
   /** A compaction reader for MapFile */
-  class MapFileCompactionReader implements CompactionReader {
+  static class MapFileCompactionReader implements CompactionReader {
     final MapFile.Reader reader;
     
     MapFileCompactionReader(final MapFile.Reader r) {
@@ -1114,7 +1114,7 @@ class HStore implements HConstants {
   /*
    * Data structure to hold result of a look at store file sizes.
    */
-  class HStoreSize {
+  static class HStoreSize {
     final long aggregate;
     final long largest;
     boolean splitable;
@@ -1361,7 +1361,6 @@ class HStore implements HConstants {
     }
 
     /** Shut it down! */
-    @Override
     public void close() {
       if(! scannerClosed) {
         try {

src/contrib/hbase/src/java/org/apache/hadoop/hbase/HTable.java

@@ -26,6 +26,7 @@ import java.util.Map;
 import java.util.Random;
 import java.util.SortedMap;
 import java.util.TreeMap;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.atomic.AtomicReferenceArray;
 
 import org.apache.commons.logging.Log;
@@ -52,7 +53,7 @@ public class HTable implements HConstants {
   protected final int numRetries;
   protected Random rand;
   protected volatile SortedMap<Text, HRegionLocation> tableServers;
-  protected BatchUpdate batch;
+  protected AtomicReference<BatchUpdate> batch;
   
   // For row mutation operations
   
@@ -79,7 +80,7 @@ public class HTable implements HConstants {
     this.numRetries = conf.getInt("hbase.client.retries.number", 5);
     this.rand = new Random();
     tableServers = connection.getTableServers(tableName);
-    this.batch = null;
+    this.batch = new AtomicReference<BatchUpdate>();
     closed = false;
   }
 
@@ -113,7 +114,7 @@ public class HTable implements HConstants {
   public synchronized void close() {
     closed = true;
     tableServers = null;
-    batch = null;
+    batch.set(null);
     connection.close(tableName);
   }
   
@@ -136,11 +137,11 @@ public class HTable implements HConstants {
    */
   private void updateInProgress(boolean updateMustBeInProgress) {
     if (updateMustBeInProgress) {
-      if (batch == null) {
+      if (batch.get() == null) {
         throw new IllegalStateException("no update in progress");
       }
     } else {
-      if (batch != null) {
+      if (batch.get() != null) {
         throw new IllegalStateException("update in progress");
       }
     }
@@ -508,8 +509,8 @@ public class HTable implements HConstants {
   public synchronized long startUpdate(final Text row) {
     checkClosed();
     updateInProgress(false);
-    batch = new BatchUpdate();
-    return batch.startUpdate(row);
+    batch.set(new BatchUpdate(rand.nextLong()));
+    return batch.get().startUpdate(row);
   }
   
   /** 
@@ -526,7 +527,7 @@ public class HTable implements HConstants {
       throw new IllegalArgumentException("value cannot be null");
     }
     updateInProgress(true);
-    batch.put(lockid, column, val);
+    batch.get().put(lockid, column, val);
   }
   
   /** 
@@ -538,7 +539,7 @@ public class HTable implements HConstants {
   public void delete(long lockid, Text column) {
     checkClosed();
     updateInProgress(true);
-    batch.delete(lockid, column);
+    batch.get().delete(lockid, column);
   }
   
   /** 
@@ -549,10 +550,10 @@ public class HTable implements HConstants {
   public synchronized void abort(long lockid) {
     checkClosed();
     updateInProgress(true);
-    if (batch.getLockid() != lockid) {
+    if (batch.get().getLockid() != lockid) {
       throw new IllegalArgumentException("invalid lock id " + lockid);
     }
-    batch = null;
+    batch.set(null);
   }
   
   /** 
@@ -577,18 +578,18 @@ public class HTable implements HConstants {
     
     checkClosed();
     updateInProgress(true);
-    if (batch.getLockid() != lockid) {
+    if (batch.get().getLockid() != lockid) {
       throw new IllegalArgumentException("invalid lock id " + lockid);
     }
     
     try {
       for (int tries = 0; tries < numRetries; tries++) {
-        HRegionLocation r = getRegionLocation(batch.getRow());
+        HRegionLocation r = getRegionLocation(batch.get().getRow());
         HRegionInterface server =
           connection.getHRegionConnection(r.getServerAddress());
         try {
           server.batchUpdate(r.getRegionInfo().getRegionName(), timestamp,
-            batch);
+            batch.get());
           break;
         } catch (IOException e) {
           if (e instanceof RemoteException) {
@@ -612,7 +613,7 @@ public class HTable implements HConstants {
         }
       }
     } finally {
-      batch = null;
+      batch.set(null);
     }
   }
   

src/contrib/hbase/src/java/org/apache/hadoop/hbase/Leases.java

@@ -63,6 +63,10 @@ public class Leases {
     this.leaseMonitor = new LeaseMonitor();
     this.leaseMonitorThread = new Thread(leaseMonitor);
     this.leaseMonitorThread.setName("Lease.monitor");
+  }
+  
+  /** Starts the lease monitor */
+  public void start() {
     leaseMonitorThread.start();
   }
 

src/contrib/hbase/src/java/org/apache/hadoop/hbase/io/BatchUpdate.java

@@ -24,7 +24,6 @@ import java.io.DataOutput;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Iterator;
-import java.util.Random;
 
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.io.Writable;
@@ -38,25 +37,33 @@ import org.apache.hadoop.io.Writable;
  */
 public class BatchUpdate implements Writable, Iterable<BatchOperation> {
   
-  // used to generate lock ids
-  private Random rand;
-
   // the row being updated
   private Text row;
   
-  // the lockid
-  private long lockid;
+  // the lockid - not used on server side
+  private transient long lockid;
   
   // the batched operations
   private ArrayList<BatchOperation> operations;
   
-  /** constructor */
+  /** Default constructor - used by Writable. */
   public BatchUpdate() {
-    this.rand = new Random();
     this.row = new Text();
     this.lockid = -1L;
     this.operations = new ArrayList<BatchOperation>();
   }
+  
+  /**
+   * Client side constructor. Clients need to provide the lockid by some means
+   * such as Random.nextLong()
+   * 
+   * @param lockid
+   */
+  public BatchUpdate(long lockid) {
+    this.row = new Text();
+    this.lockid = Long.valueOf(Math.abs(lockid));
+    this.operations = new ArrayList<BatchOperation>();
+  }
 
   /** @return the lock id */
   public long getLockid() {
@@ -84,7 +91,6 @@ public class BatchUpdate implements Writable, Iterable<BatchOperation> {
    */
   public synchronized long startUpdate(final Text row) {
     this.row = row;
-    this.lockid = Long.valueOf(Math.abs(rand.nextLong()));
     return this.lockid;
   }
   

src/contrib/hbase/src/java/org/apache/hadoop/hbase/mapred/TableMap.java

@@ -71,12 +71,6 @@ public abstract class TableMap extends MapReduceBase implements Mapper {
     job.set(TableInputFormat.COLUMN_LIST, columns);
   }
 
-  /** {@inheritDoc} */
-  @Override
-  public void configure(JobConf job) {
-    super.configure(job);
-  }
-
   /**
    * Input:
    * @param key is of type HStoreKey