[SPARK-13823][SPARK-13397][SPARK-13395][CORE] More warnings, StandardCharset follow up

## What changes were proposed in this pull request?

Follow up to https://github.com/apache/spark/pull/11657

- Also update `String.getBytes("UTF-8")` to use `StandardCharsets.UTF_8`
- And fix one last new Coverity warning that turned up (use of unguarded `wait()` replaced by simpler/more robust `java.util.concurrent` classes in tests)
- And while we're here cleaning up Coverity warnings, just fix about 15 more build warnings

## How was this patch tested?

Jenkins tests

Author: Sean Owen <sowen@cloudera.com>

Closes #11725 from srowen/SPARK-13823.2.

8 files changed, 93 insertions, 104 deletions

diff --git a/common/network-common/src/test/java/org/apache/spark/network/RequestTimeoutIntegrationSuite.java b/common/network-common/src/test/java/org/apache/spark/network/RequestTimeoutIntegrationSuite.java
index c0ff9dc5f5..dd0171d1d1 100644
--- a/common/network-common/src/test/java/org/apache/spark/network/RequestTimeoutIntegrationSuite.java
+++ b/common/network-common/src/test/java/org/apache/spark/network/RequestTimeoutIntegrationSuite.java
@@ -36,6 +36,7 @@ import static org.junit.Assert.*;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.*;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Semaphore;
 import java.util.concurrent.TimeUnit;
 
@@ -93,7 +94,7 @@ public class RequestTimeoutIntegrationSuite {
           ByteBuffer message,
           RpcResponseCallback callback) {
         try {
-          semaphore.tryAcquire(FOREVER, TimeUnit.MILLISECONDS);
+          semaphore.acquire();
           callback.onSuccess(ByteBuffer.allocate(responseSize));
         } catch (InterruptedException e) {
           // do nothing
@@ -113,20 +114,17 @@ public class RequestTimeoutIntegrationSuite {
 
     // First completes quickly (semaphore starts at 1).
     TestCallback callback0 = new TestCallback();
-    synchronized (callback0) {
-      client.sendRpc(ByteBuffer.allocate(0), callback0);
-      callback0.wait(FOREVER);
-      assertEquals(responseSize, callback0.successLength);
-    }
+    client.sendRpc(ByteBuffer.allocate(0), callback0);
+    callback0.latch.await();
+    assertEquals(responseSize, callback0.successLength);
 
     // Second times out after 2 seconds, with slack. Must be IOException.
     TestCallback callback1 = new TestCallback();
-    synchronized (callback1) {
-      client.sendRpc(ByteBuffer.allocate(0), callback1);
-      callback1.wait(4 * 1000);
-      assertNotNull(callback1.failure);
-      assertTrue(callback1.failure instanceof IOException);
-    }
+    client.sendRpc(ByteBuffer.allocate(0), callback1);
+    callback1.latch.await(4, TimeUnit.SECONDS);
+    assertNotNull(callback1.failure);
+    assertTrue(callback1.failure instanceof IOException);
+
     semaphore.release();
   }
 
@@ -143,7 +141,7 @@ public class RequestTimeoutIntegrationSuite {
           ByteBuffer message,
           RpcResponseCallback callback) {
         try {
-          semaphore.tryAcquire(FOREVER, TimeUnit.MILLISECONDS);
+          semaphore.acquire();
           callback.onSuccess(ByteBuffer.allocate(responseSize));
         } catch (InterruptedException e) {
           // do nothing
@@ -164,24 +162,20 @@ public class RequestTimeoutIntegrationSuite {
     TransportClient client0 =
       clientFactory.createClient(TestUtils.getLocalHost(), server.getPort());
     TestCallback callback0 = new TestCallback();
-    synchronized (callback0) {
-      client0.sendRpc(ByteBuffer.allocate(0), callback0);
-      callback0.wait(FOREVER);
-      assertTrue(callback0.failure instanceof IOException);
-      assertFalse(client0.isActive());
-    }
+    client0.sendRpc(ByteBuffer.allocate(0), callback0);
+    callback0.latch.await();
+    assertTrue(callback0.failure instanceof IOException);
+    assertFalse(client0.isActive());
 
     // Increment the semaphore and the second request should succeed quickly.
     semaphore.release(2);
     TransportClient client1 =
       clientFactory.createClient(TestUtils.getLocalHost(), server.getPort());
     TestCallback callback1 = new TestCallback();
-    synchronized (callback1) {
-      client1.sendRpc(ByteBuffer.allocate(0), callback1);
-      callback1.wait(FOREVER);
-      assertEquals(responseSize, callback1.successLength);
-      assertNull(callback1.failure);
-    }
+    client1.sendRpc(ByteBuffer.allocate(0), callback1);
+    callback1.latch.await();
+    assertEquals(responseSize, callback1.successLength);
+    assertNull(callback1.failure);
   }
 
   // The timeout is relative to the LAST request sent, which is kinda weird, but still.
@@ -226,18 +220,14 @@ public class RequestTimeoutIntegrationSuite {
     client.fetchChunk(0, 1, callback1);
     Uninterruptibles.sleepUninterruptibly(1200, TimeUnit.MILLISECONDS);
 
-    synchronized (callback0) {
-      // not complete yet, but should complete soon
-      assertEquals(-1, callback0.successLength);
-      assertNull(callback0.failure);
-      callback0.wait(2 * 1000);
-      assertTrue(callback0.failure instanceof IOException);
-    }
+    // not complete yet, but should complete soon
+    assertEquals(-1, callback0.successLength);
+    assertNull(callback0.failure);
+    callback0.latch.await(2, TimeUnit.SECONDS);
+    assertTrue(callback0.failure instanceof IOException);
 
-    synchronized (callback1) {
-      // failed at same time as previous
-      assertTrue(callback0.failure instanceof IOException);
-    }
+    // failed at same time as previous
+    assertTrue(callback1.failure instanceof IOException);
   }
 
   /**
@@ -248,41 +238,35 @@ public class RequestTimeoutIntegrationSuite {
 
     int successLength = -1;
     Throwable failure;
+    final CountDownLatch latch = new CountDownLatch(1);
 
     @Override
     public void onSuccess(ByteBuffer response) {
-      synchronized(this) {
-        successLength = response.remaining();
-        this.notifyAll();
-      }
+      successLength = response.remaining();
+      latch.countDown();
     }
 
     @Override
     public void onFailure(Throwable e) {
-      synchronized(this) {
-        failure = e;
-        this.notifyAll();
-      }
+      failure = e;
+      latch.countDown();
     }
 
     @Override
     public void onSuccess(int chunkIndex, ManagedBuffer buffer) {
-      synchronized(this) {
-        try {
-          successLength = buffer.nioByteBuffer().remaining();
-          this.notifyAll();
-        } catch (IOException e) {
-          // weird
-        }
+      try {
+        successLength = buffer.nioByteBuffer().remaining();
+      } catch (IOException e) {
+        // weird
+      } finally {
+        latch.countDown();
       }
     }
 
     @Override
     public void onFailure(int chunkIndex, Throwable e) {
-      synchronized(this) {
-        failure = e;
-        this.notifyAll();
-      }
+      failure = e;
+      latch.countDown();
     }
   }
 }
diff --git a/common/network-common/src/test/java/org/apache/spark/network/sasl/SparkSaslSuite.java b/common/network-common/src/test/java/org/apache/spark/network/sasl/SparkSaslSuite.java
index 045773317a..45cc03df43 100644
--- a/common/network-common/src/test/java/org/apache/spark/network/sasl/SparkSaslSuite.java
+++ b/common/network-common/src/test/java/org/apache/spark/network/sasl/SparkSaslSuite.java
@@ -26,6 +26,7 @@ import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Random;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeoutException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;
@@ -276,7 +277,7 @@ public class SparkSaslSuite {
 
       ctx = new SaslTestCtx(rpcHandler, true, false);
 
-      final Object lock = new Object();
+      final CountDownLatch lock = new CountDownLatch(1);
 
       ChunkReceivedCallback callback = mock(ChunkReceivedCallback.class);
       doAnswer(new Answer<Void>() {
@@ -284,17 +285,13 @@ public class SparkSaslSuite {
           public Void answer(InvocationOnMock invocation) {
             response.set((ManagedBuffer) invocation.getArguments()[1]);
             response.get().retain();
-            synchronized (lock) {
-              lock.notifyAll();
-            }
+            lock.countDown();
             return null;
           }
         }).when(callback).onSuccess(anyInt(), any(ManagedBuffer.class));
 
-      synchronized (lock) {
-        ctx.client.fetchChunk(0, 0, callback);
-        lock.wait(10 * 1000);
-      }
+      ctx.client.fetchChunk(0, 0, callback);
+      lock.await(10, TimeUnit.SECONDS);
 
       verify(callback, times(1)).onSuccess(anyInt(), any(ManagedBuffer.class));
       verify(callback, never()).onFailure(anyInt(), any(Throwable.class));
diff --git a/common/network-shuffle/src/test/java/org/apache/spark/network/sasl/SaslIntegrationSuite.java b/common/network-shuffle/src/test/java/org/apache/spark/network/sasl/SaslIntegrationSuite.java
index 0ea631ea14..5322fcd781 100644
--- a/common/network-shuffle/src/test/java/org/apache/spark/network/sasl/SaslIntegrationSuite.java
+++ b/common/network-shuffle/src/test/java/org/apache/spark/network/sasl/SaslIntegrationSuite.java
@@ -20,6 +20,7 @@ package org.apache.spark.network.sasl;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicReference;
 
 import com.google.common.collect.Lists;
@@ -197,26 +198,23 @@ public class SaslIntegrationSuite {
 
       final AtomicReference<Throwable> exception = new AtomicReference<>();
 
+      final CountDownLatch blockFetchLatch = new CountDownLatch(1);
       BlockFetchingListener listener = new BlockFetchingListener() {
         @Override
-        public synchronized void onBlockFetchSuccess(String blockId, ManagedBuffer data) {
-          notifyAll();
+        public void onBlockFetchSuccess(String blockId, ManagedBuffer data) {
+          blockFetchLatch.countDown();
         }
-
         @Override
-        public synchronized void onBlockFetchFailure(String blockId, Throwable t) {
+        public void onBlockFetchFailure(String blockId, Throwable t) {
           exception.set(t);
-          notifyAll();
+          blockFetchLatch.countDown();
         }
       };
 
-      String[] blockIds = new String[] { "shuffle_2_3_4", "shuffle_6_7_8" };
-      OneForOneBlockFetcher fetcher = new OneForOneBlockFetcher(client1, "app-2", "0",
-        blockIds, listener);
-      synchronized (listener) {
-        fetcher.start();
-        listener.wait();
-      }
+      String[] blockIds = { "shuffle_2_3_4", "shuffle_6_7_8" };
+      OneForOneBlockFetcher fetcher = new OneForOneBlockFetcher(client1, "app-2", "0", blockIds, listener);
+      fetcher.start();
+      blockFetchLatch.await();
       checkSecurityException(exception.get());
 
       // Register an executor so that the next steps work.
@@ -240,24 +238,22 @@ public class SaslIntegrationSuite {
       client2 = clientFactory2.createClient(TestUtils.getLocalHost(),
         blockServer.getPort());
 
+      final CountDownLatch chunkReceivedLatch = new CountDownLatch(1);
       ChunkReceivedCallback callback = new ChunkReceivedCallback() {
         @Override
-        public synchronized void onSuccess(int chunkIndex, ManagedBuffer buffer) {
-          notifyAll();
+        public void onSuccess(int chunkIndex, ManagedBuffer buffer) {
+          chunkReceivedLatch.countDown();
         }
-
         @Override
-        public synchronized void onFailure(int chunkIndex, Throwable t) {
+        public void onFailure(int chunkIndex, Throwable t) {
           exception.set(t);
-          notifyAll();
+          chunkReceivedLatch.countDown();
         }
       };
 
       exception.set(null);
-      synchronized (callback) {
-        client2.fetchChunk(streamId, 0, callback);
-        callback.wait();
-      }
+      client2.fetchChunk(streamId, 0, callback);
+      chunkReceivedLatch.await();
       checkSecurityException(exception.get());
     } finally {
       if (client1 != null) {
diff --git a/common/sketch/pom.xml b/common/sketch/pom.xml
index 442043cb51..8bc1f52798 100644
--- a/common/sketch/pom.xml
+++ b/common/sketch/pom.xml
@@ -45,5 +45,29 @@
   <build>
     <outputDirectory>target/scala-${scala.binary.version}/classes</outputDirectory>
     <testOutputDirectory>target/scala-${scala.binary.version}/test-classes</testOutputDirectory>
+    <pluginManagement>
+      <plugins>
+        <plugin>
+          <groupId>net.alchim31.maven</groupId>
+          <artifactId>scala-maven-plugin</artifactId>
+          <configuration>
+            <javacArgs combine.children="append">
+              <!-- This option is needed to suppress warnings from sun.misc.Unsafe usage -->
+              <javacArg>-XDignore.symbol.file</javacArg>
+            </javacArgs>
+          </configuration>
+        </plugin>
+        <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-compiler-plugin</artifactId>
+          <configuration>
+            <compilerArgs combine.children="append">
+              <!-- This option is needed to suppress warnings from sun.misc.Unsafe usage -->
+              <arg>-XDignore.symbol.file</arg>
+            </compilerArgs>
+          </configuration>
+        </plugin>
+      </plugins>
+    </pluginManagement>
   </build>
 </project>
diff --git a/common/sketch/src/main/java/org/apache/spark/util/sketch/Utils.java b/common/sketch/src/main/java/org/apache/spark/util/sketch/Utils.java
index feb601d44f..81461f0300 100644
--- a/common/sketch/src/main/java/org/apache/spark/util/sketch/Utils.java
+++ b/common/sketch/src/main/java/org/apache/spark/util/sketch/Utils.java
@@ -17,15 +17,11 @@
 
 package org.apache.spark.util.sketch;
 
-import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
 
 class Utils {
   public static byte[] getBytesFromUTF8String(String str) {
-    try {
-      return str.getBytes("utf-8");
-    } catch (UnsupportedEncodingException e) {
-      throw new IllegalArgumentException("Only support utf-8 string", e);
-    }
+    return str.getBytes(StandardCharsets.UTF_8);
   }
 
   public static long integralToLong(Object i) {
diff --git a/common/unsafe/pom.xml b/common/unsafe/pom.xml
index 5250014739..93b9580f26 100644
--- a/common/unsafe/pom.xml
+++ b/common/unsafe/pom.xml
@@ -98,7 +98,7 @@
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-compiler-plugin</artifactId>
           <configuration>
-            <compilerArgs>
+            <compilerArgs combine.children="append">
               <!-- This option is needed to suppress warnings from sun.misc.Unsafe usage -->
               <arg>-XDignore.symbol.file</arg>
             </compilerArgs>
diff --git a/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java b/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
index e16166ade4..54a5456924 100644
--- a/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
+++ b/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
@@ -106,15 +106,7 @@ public final class UTF8String implements Comparable<UTF8String>, Externalizable,
    * Creates an UTF8String from String.
    */
   public static UTF8String fromString(String str) {
-    if (str == null) return null;
-    try {
-      return fromBytes(str.getBytes("utf-8"));
-    } catch (UnsupportedEncodingException e) {
-      // Turn the exception into unchecked so we can find out about it at runtime, but
-      // don't need to add lots of boilerplate code everywhere.
-      throwException(e);
-      return null;
-    }
+    return str == null ? null : fromBytes(str.getBytes(StandardCharsets.UTF_8));
   }
 
   /**
diff --git a/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java b/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
index bef5d712cf..d4160ad029 100644
--- a/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
+++ b/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
@@ -17,7 +17,7 @@
 
 package org.apache.spark.unsafe.types;
 
-import java.io.UnsupportedEncodingException;
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.HashMap;
 
@@ -30,9 +30,9 @@ import static org.apache.spark.unsafe.types.UTF8String.*;
 
 public class UTF8StringSuite {
 
-  private static void checkBasic(String str, int len) throws UnsupportedEncodingException {
+  private static void checkBasic(String str, int len) {
     UTF8String s1 = fromString(str);
-    UTF8String s2 = fromBytes(str.getBytes("utf8"));
+    UTF8String s2 = fromBytes(str.getBytes(StandardCharsets.UTF_8));
     assertEquals(s1.numChars(), len);
     assertEquals(s2.numChars(), len);
 
@@ -51,7 +51,7 @@ public class UTF8StringSuite {
   }
 
   @Test
-  public void basicTest() throws UnsupportedEncodingException {
+  public void basicTest() {
     checkBasic("", 0);
     checkBasic("hello", 5);
     checkBasic("大 千 世 界", 7);