HADOOP-14400. Fix warnings from spotbugs in hadoop-tools. Contributed by Weiwei Yang.

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/NativeAzureFileSystem.java

@@ -2451,8 +2451,6 @@ public boolean mkdirs(Path f, FsPermission permission, boolean noUmask) throws I
 
 
     ArrayList<String> keysToCreateAsFolder = new ArrayList<String>();
-    ArrayList<String> keysToUpdateAsFolder = new ArrayList<String>();
-    boolean childCreated = false;
     // Check that there is no file in the parent chain of the given path.
     for (Path current = absolutePath, parent = current.getParent();
         parent != null; // Stop when you get to the root
@@ -2464,14 +2462,6 @@ public boolean mkdirs(Path f, FsPermission permission, boolean noUmask) throws I
             + current + " is an existing file.");
       } else if (currentMetadata == null) {
         keysToCreateAsFolder.add(currentKey);
-        childCreated = true;
-      } else {
-        // The directory already exists. Its last modified time need to be
-        // updated if there is a child directory created under it.
-        if (childCreated) {
-          keysToUpdateAsFolder.add(currentKey);
-        }
-        childCreated = false;
       }
     }
 

hadoop-tools/hadoop-gridmix/src/main/java/org/apache/hadoop/mapred/gridmix/InputStriper.java

@@ -131,9 +131,7 @@ private long[] toLongArray(final ArrayList<Long> sigh) {
   static final Comparator<Entry<String,Double>> hostRank =
     new Comparator<Entry<String,Double>>() {
       public int compare(Entry<String,Double> a, Entry<String,Double> b) {
-          final double va = a.getValue();
+        return Double.compare(a.getValue(), b.getValue());
-          final double vb = b.getValue();
+      }
-          return va > vb ? -1 : va < vb ? 1 : 0;
-        }
     };
 }

hadoop-tools/hadoop-gridmix/src/main/java/org/apache/hadoop/mapred/gridmix/emulators/resourceusage/TotalHeapUsageEmulatorPlugin.java

@@ -19,6 +19,8 @@
 
 import java.io.IOException;
 import java.util.ArrayList;
+
+import com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.mapred.gridmix.Progressive;
 import org.apache.hadoop.tools.rumen.ResourceUsageMetrics;
@@ -129,7 +131,7 @@ public void initialize(ResourceCalculatorPlugin monitor,
   public static class DefaultHeapUsageEmulator 
   implements HeapUsageEmulatorCore {
     // store the unit loads in a list
-    protected static final ArrayList<Object> heapSpace =
+    private static final ArrayList<Object> heapSpace =
         new ArrayList<Object>();
     
     /**
@@ -142,7 +144,17 @@ public void load(long sizeInMB) {
         heapSpace.add((Object)new byte[ONE_MB]);
       }
     }
-    
+
+    /**
+     * Gets the total number of 1mb objects stored in the emulator.
+     *
+     * @return total number of 1mb objects.
+     */
+    @VisibleForTesting
+    public int getHeapSpaceSize() {
+      return heapSpace.size();
+    }
+
     /**
      * This will initialize the core and check if the core can emulate the 
      * desired target on the underlying hardware.

hadoop-tools/hadoop-gridmix/src/test/java/org/apache/hadoop/mapred/gridmix/TestGridmixMemoryEmulation.java

@@ -58,7 +58,7 @@ int getNumCalls() {
     
     // Get the total number of 1mb objects stored within
     long getHeapUsageInMB() {
-      return heapSpace.size();
+      return getHeapSpaceSize();
     }
     
     @Override

hadoop-tools/hadoop-rumen/src/main/java/org/apache/hadoop/tools/rumen/datatypes/util/MapReduceJobPropertiesParser.java

@@ -130,7 +130,7 @@ public DataType<?> parseJobProperty(String key, String value) {
   /**
    * Extracts the -Xmx heap option from the specified string.
    */
-  public static void extractMaxHeapOpts(String javaOptions, 
+  public static void extractMaxHeapOpts(final String javaOptions,
                                         List<String> heapOpts, 
                                         List<String> others) {
     for (String opt : javaOptions.split(" ")) {
@@ -160,6 +160,7 @@ public static void extractMinHeapOpts(String javaOptions,
   
   // Maps the value of the specified key.
   private DataType<?> fromString(String key, String value) {
+    DefaultDataType defaultValue = new DefaultDataType(value);
     if (value != null) {
       // check known configs
       //  job-name
@@ -190,14 +191,13 @@ private DataType<?> fromString(String key, String value) {
       // check if the config parameter represents a number
       try {
         format.parse(value);
-        return new DefaultDataType(value);
+        return defaultValue;
       } catch (ParseException pe) {}
 
       // check if the config parameters represents a boolean 
       // avoiding exceptions
       if ("true".equals(value) || "false".equals(value)) {
-        Boolean.parseBoolean(value);
+        return defaultValue;
-        return new DefaultDataType(value);
       }
 
       // check if the config parameter represents a class
@@ -208,7 +208,7 @@ private DataType<?> fromString(String key, String value) {
       // handle distributed cache sizes and timestamps
       if (latestKey.endsWith("sizes") 
           || latestKey.endsWith(".timestamps")) {
-        new DefaultDataType(value);
+        return defaultValue;
       }
       
       // check if the config parameter represents a file-system path

hadoop-tools/hadoop-sls/src/main/java/org/apache/hadoop/yarn/sls/SLSRunner.java

@@ -32,6 +32,7 @@
 import java.util.Map;
 import java.util.Random;
 import java.util.Set;
+import java.util.Collections;
 import java.util.concurrent.ConcurrentHashMap;
 
 import com.fasterxml.jackson.core.JsonFactory;
@@ -113,7 +114,8 @@ public class SLSRunner extends Configured implements Tool {
   // other simulation information
   private int numNMs, numRacks, numAMs, numTasks;
   private long maxRuntime;
-  public final static Map<String, Object> simulateInfoMap =
+
+  private final static Map<String, Object> simulateInfoMap =
           new HashMap<String, Object>();
 
   // logger
@@ -165,6 +167,13 @@ private void init(Configuration tempConf) throws ClassNotFoundException {
     }
   }
 
+  /**
+   * @return an unmodifiable view of the simulated info map.
+   */
+  public static Map<String, Object> getSimulateInfoMap() {
+    return Collections.unmodifiableMap(simulateInfoMap);
+  }
+
   public void setSimulationParams(TraceType inType, String[] inTraces,
       String nodes, String outDir, Set<String> trackApps,
       boolean printsimulation) throws IOException, ClassNotFoundException {

hadoop-tools/hadoop-sls/src/main/java/org/apache/hadoop/yarn/sls/scheduler/FairSchedulerMetrics.java

@@ -180,16 +180,16 @@ public void trackQueue(String queueName) {
       new Gauge<Long>() {
         @Override
         public Long getValue() {
-          if (! maxReset &&
+          if (! maxReset
-                  SLSRunner.simulateInfoMap.containsKey("Number of nodes") &&
+              && SLSRunner.getSimulateInfoMap().containsKey("Number of nodes")
-                  SLSRunner.simulateInfoMap.containsKey("Node memory (MB)") &&
+              && SLSRunner.getSimulateInfoMap().containsKey("Node memory (MB)")
-                  SLSRunner.simulateInfoMap.containsKey("Node VCores")) {
+              && SLSRunner.getSimulateInfoMap().containsKey("Node VCores")) {
-            int numNMs = Integer.parseInt(
+            int numNMs = Integer.parseInt(SLSRunner.getSimulateInfoMap()
-                  SLSRunner.simulateInfoMap.get("Number of nodes").toString());
+                .get("Number of nodes").toString());
-            int numMemoryMB = Integer.parseInt(
+            int numMemoryMB = Integer.parseInt(SLSRunner.getSimulateInfoMap()
-                  SLSRunner.simulateInfoMap.get("Node memory (MB)").toString());
+                .get("Node memory (MB)").toString());
-            int numVCores = Integer.parseInt(
+            int numVCores = Integer.parseInt(SLSRunner.getSimulateInfoMap()
-                  SLSRunner.simulateInfoMap.get("Node VCores").toString());
+                .get("Node VCores").toString());
 
             totalMemoryMB = numNMs * numMemoryMB;
             totalVCores = numNMs * numVCores;

hadoop-tools/hadoop-sls/src/main/java/org/apache/hadoop/yarn/sls/web/SLSWebApp.java

@@ -187,14 +187,14 @@ private void printPageIndex(HttpServletRequest request,
     response.setStatus(HttpServletResponse.SC_OK);
 
     String simulateInfo;
-    if (SLSRunner.simulateInfoMap.isEmpty()) {
+    if (SLSRunner.getSimulateInfoMap().isEmpty()) {
       String empty = "<tr><td colspan='2' align='center'>" +
               "No information available</td></tr>";
       simulateInfo = MessageFormat.format(simulateInfoTemplate, empty);
     } else {
       StringBuilder info = new StringBuilder();
       for (Map.Entry<String, Object> entry :
-              SLSRunner.simulateInfoMap.entrySet()) {
+              SLSRunner.getSimulateInfoMap().entrySet()) {
         info.append("<tr>");
         info.append("<td class='td1'>").append(entry.getKey()).append("</td>");
         info.append("<td class='td2'>").append(entry.getValue())

hadoop-tools/hadoop-sls/src/test/java/org/apache/hadoop/yarn/sls/web/TestSLSWebApp.java

@@ -20,7 +20,6 @@
 
 import org.junit.Assert;
 import org.apache.commons.io.FileUtils;
-import org.apache.hadoop.yarn.sls.SLSRunner;
 import org.junit.Test;
 
 import java.io.File;
@@ -28,6 +27,7 @@
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
+import java.util.HashMap;
 
 public class TestSLSWebApp {
 
@@ -36,20 +36,21 @@ public void testSimulateInfoPageHtmlTemplate() throws Exception {
     String simulateInfoTemplate = FileUtils.readFileToString(
             new File("src/main/html/simulate.info.html.template"));
 
-    SLSRunner.simulateInfoMap.put("Number of racks", 10);
+    Map<String, Object> simulateInfoMap = new HashMap<>();
-    SLSRunner.simulateInfoMap.put("Number of nodes", 100);
+    simulateInfoMap.put("Number of racks", 10);
-    SLSRunner.simulateInfoMap.put("Node memory (MB)", 1024);
+    simulateInfoMap.put("Number of nodes", 100);
-    SLSRunner.simulateInfoMap.put("Node VCores", 1);
+    simulateInfoMap.put("Node memory (MB)", 1024);
-    SLSRunner.simulateInfoMap.put("Number of applications", 100);
+    simulateInfoMap.put("Node VCores", 1);
-    SLSRunner.simulateInfoMap.put("Number of tasks", 1000);
+    simulateInfoMap.put("Number of applications", 100);
-    SLSRunner.simulateInfoMap.put("Average tasks per applicaion", 10);
+    simulateInfoMap.put("Number of tasks", 1000);
-    SLSRunner.simulateInfoMap.put("Number of queues", 4);
+    simulateInfoMap.put("Average tasks per applicaion", 10);
-    SLSRunner.simulateInfoMap.put("Average applications per queue", 25);
+    simulateInfoMap.put("Number of queues", 4);
-    SLSRunner.simulateInfoMap.put("Estimated simulate time (s)", 10000);
+    simulateInfoMap.put("Average applications per queue", 25);
+    simulateInfoMap.put("Estimated simulate time (s)", 10000);
 
     StringBuilder info = new StringBuilder();
     for (Map.Entry<String, Object> entry :
-            SLSRunner.simulateInfoMap.entrySet()) {
+        simulateInfoMap.entrySet()) {
       info.append("<tr>");
       info.append("<td class='td1'>" + entry.getKey() + "</td>");
       info.append("<td class='td2'>" + entry.getValue() + "</td>");
@@ -60,8 +61,7 @@ public void testSimulateInfoPageHtmlTemplate() throws Exception {
             MessageFormat.format(simulateInfoTemplate, info.toString());
     Assert.assertTrue("The simulate info html page should not be empty",
             simulateInfo.length() > 0);
-    for (Map.Entry<String, Object> entry :
+    for (Map.Entry<String, Object> entry : simulateInfoMap.entrySet()) {
-            SLSRunner.simulateInfoMap.entrySet()) {
       Assert.assertTrue("The simulate info html page should have information "
               + "of " + entry.getKey(), simulateInfo.contains("<td class='td1'>"
               + entry.getKey() + "</td><td class='td2'>"