HBASE-27234 Clean up error-prone warnings in hbase-examples

Close #4647

Co-authored-by: Duo Zhang <zhangduo@apache.org>
Signed-off-by: Duo Zhang <zhangduo@apache.org>
Signed-off-by: Viraj Jasani <vjasani@apache.org>

hbase-examples/src/main/java/org/apache/hadoop/hbase/client/example/HttpProxyExample.java

@@ -22,6 +22,8 @@ import static org.apache.hadoop.hbase.util.NettyFutureUtils.safeWriteAndFlush;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.util.Iterator;
+import java.util.List;
 import java.util.concurrent.ExecutionException;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
@@ -35,6 +37,7 @@ import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.yetus.audience.InterfaceAudience;
 
 import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
+import org.apache.hbase.thirdparty.com.google.common.base.Splitter;
 import org.apache.hbase.thirdparty.com.google.common.base.Throwables;
 import org.apache.hbase.thirdparty.io.netty.bootstrap.ServerBootstrap;
 import org.apache.hbase.thirdparty.io.netty.buffer.ByteBuf;
@@ -158,12 +161,20 @@ public class HttpProxyExample {
     }
 
     private Params parse(FullHttpRequest req) {
-      String[] components = new QueryStringDecoder(req.uri()).path().split("/");
+      List<String> components =
-      Preconditions.checkArgument(components.length == 4, "Unrecognized uri: %s", req.uri());
+        Splitter.on('/').splitToList(new QueryStringDecoder(req.uri()).path());
+      Preconditions.checkArgument(components.size() == 4, "Unrecognized uri: %s", req.uri());
+      Iterator<String> i = components.iterator();
       // path is start with '/' so split will give an empty component
-      String[] cfAndCq = components[3].split(":");
+      i.next();
-      Preconditions.checkArgument(cfAndCq.length == 2, "Unrecognized uri: %s", req.uri());
+      String table = i.next();
-      return new Params(components[1], components[2], cfAndCq[0], cfAndCq[1]);
+      String row = i.next();
+      List<String> cfAndCq = Splitter.on(':').splitToList(i.next());
+      Preconditions.checkArgument(cfAndCq.size() == 2, "Unrecognized uri: %s", req.uri());
+      i = cfAndCq.iterator();
+      String family = i.next();
+      String qualifier = i.next();
+      return new Params(table, row, family, qualifier);
     }
 
     private void get(ChannelHandlerContext ctx, FullHttpRequest req) {

hbase-examples/src/main/java/org/apache/hadoop/hbase/client/example/MultiThreadedClientExample.java

@@ -30,7 +30,6 @@ import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.TimeUnit;
 import org.apache.hadoop.conf.Configured;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.Cell.Type;
 import org.apache.hadoop.hbase.CellBuilderFactory;
 import org.apache.hadoop.hbase.CellBuilderType;
 import org.apache.hadoop.hbase.TableName;
@@ -240,7 +239,7 @@ public class MultiThreadedClientExample extends Configured implements Tool {
         byte[] rk = Bytes.toBytes(ThreadLocalRandom.current().nextLong());
         Put p = new Put(rk);
         p.add(CellBuilderFactory.create(CellBuilderType.SHALLOW_COPY).setRow(rk).setFamily(FAMILY)
-          .setQualifier(QUAL).setTimestamp(p.getTimestamp()).setType(Type.Put).setValue(value)
+          .setQualifier(QUAL).setTimestamp(p.getTimestamp()).setType(Cell.Type.Put).setValue(value)
           .build());
         t.put(p);
       }

hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/BulkDeleteEndpoint.java

@@ -28,7 +28,6 @@ import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CoprocessorEnvironment;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.HConstants.OperationStatusCode;
 import org.apache.hadoop.hbase.client.Delete;
 import org.apache.hadoop.hbase.client.Mutation;
 import org.apache.hadoop.hbase.client.Scan;
@@ -52,7 +51,6 @@ import org.apache.hbase.thirdparty.com.google.protobuf.Service;
 import org.apache.hadoop.hbase.shaded.coprocessor.example.generated.BulkDeleteProtos.BulkDeleteRequest;
 import org.apache.hadoop.hbase.shaded.coprocessor.example.generated.BulkDeleteProtos.BulkDeleteRequest.DeleteType;
 import org.apache.hadoop.hbase.shaded.coprocessor.example.generated.BulkDeleteProtos.BulkDeleteResponse;
-import org.apache.hadoop.hbase.shaded.coprocessor.example.generated.BulkDeleteProtos.BulkDeleteResponse.Builder;
 import org.apache.hadoop.hbase.shaded.coprocessor.example.generated.BulkDeleteProtos.BulkDeleteService;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 
@@ -157,7 +155,7 @@ public class BulkDeleteEndpoint extends BulkDeleteService implements RegionCopro
           }
           OperationStatus[] opStatus = region.batchMutate(deleteArr);
           for (i = 0; i < opStatus.length; i++) {
-            if (opStatus[i].getOperationStatusCode() != OperationStatusCode.SUCCESS) {
+            if (opStatus[i].getOperationStatusCode() != HConstants.OperationStatusCode.SUCCESS) {
               break;
             }
             totalRowsDeleted++;
@@ -183,7 +181,7 @@ public class BulkDeleteEndpoint extends BulkDeleteService implements RegionCopro
         }
       }
     }
-    Builder responseBuilder = BulkDeleteResponse.newBuilder();
+    BulkDeleteResponse.Builder responseBuilder = BulkDeleteResponse.newBuilder();
     responseBuilder.setRowsDeleted(totalRowsDeleted);
     if (deleteType == DeleteType.VERSION) {
       responseBuilder.setVersionsDeleted(totalVersionsDeleted);

hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/ExampleRegionObserverWithMetrics.java

@@ -109,6 +109,8 @@ public class ExampleRegionObserverWithMetrics implements RegionCoprocessor {
         // simulate the operation by sleeping.
         Thread.sleep(ThreadLocalRandom.current().nextLong(100));
       } catch (InterruptedException ignore) {
+        // Restore the interrupt status
+        Thread.currentThread().interrupt();
       }
     }
   }

hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/RowCountEndpoint.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.CoprocessorEnvironment;
@@ -34,6 +35,7 @@ import org.apache.hadoop.hbase.regionserver.InternalScanner;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.yetus.audience.InterfaceAudience;
 
+import org.apache.hbase.thirdparty.com.google.common.collect.Iterables;
 import org.apache.hbase.thirdparty.com.google.protobuf.RpcCallback;
 import org.apache.hbase.thirdparty.com.google.protobuf.RpcController;
 import org.apache.hbase.thirdparty.com.google.protobuf.Service;
@@ -97,10 +99,7 @@ public class RowCountEndpoint extends RowCountService implements RegionCoprocess
       CoprocessorRpcUtils.setControllerException(controller, ioe);
     } finally {
       if (scanner != null) {
-        try {
+        IOUtils.closeQuietly(scanner);
-          scanner.close();
-        } catch (IOException ignored) {
-        }
       }
     }
     done.run(response);
@@ -121,21 +120,15 @@ public class RowCountEndpoint extends RowCountService implements RegionCoprocess
       long count = 0;
       do {
         hasMore = scanner.next(results);
-        for (Cell kv : results) {
+        count += Iterables.size(results);
-          count++;
-        }
         results.clear();
       } while (hasMore);
-
       response = CountResponse.newBuilder().setCount(count).build();
     } catch (IOException ioe) {
       CoprocessorRpcUtils.setControllerException(controller, ioe);
     } finally {
       if (scanner != null) {
-        try {
+        IOUtils.closeQuietly(scanner);
-          scanner.close();
-        } catch (IOException ignored) {
-        }
       }
     }
     done.run(response);

hbase-examples/src/main/java/org/apache/hadoop/hbase/mapreduce/IndexBuilder.java

@@ -131,6 +131,7 @@ public class IndexBuilder extends Configured implements Tool {
     return job;
   }
 
+  @Override
   public int run(String[] args) throws Exception {
     Configuration conf = HBaseConfiguration.create(getConf());
     if (args.length < 3) {

hbase-examples/src/main/java/org/apache/hadoop/hbase/mapreduce/SampleUploader.java

@@ -18,6 +18,8 @@
 package org.apache.hadoop.hbase.mapreduce;
 
 import java.io.IOException;
+import java.util.Iterator;
+import java.util.List;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
 import org.apache.hadoop.fs.Path;
@@ -37,6 +39,8 @@ import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import org.apache.hbase.thirdparty.com.google.common.base.Splitter;
+
 /**
  * Sample Uploader MapReduce
  * <p>
@@ -80,16 +84,16 @@ public class SampleUploader extends Configured implements Tool {
       // Each line is comma-delimited; row,family,qualifier,value
 
       // Split CSV line
-      String[] values = line.toString().split(",");
+      List<String> values = Splitter.on(',').splitToList(line.toString());
-      if (values.length != 4) {
+      if (values.size() != 4) {
         return;
       }
-
+      Iterator<String> i = values.iterator();
       // Extract each value
-      byte[] row = Bytes.toBytes(values[0]);
+      byte[] row = Bytes.toBytes(i.next());
-      byte[] family = Bytes.toBytes(values[1]);
+      byte[] family = Bytes.toBytes(i.next());
-      byte[] qualifier = Bytes.toBytes(values[2]);
+      byte[] qualifier = Bytes.toBytes(i.next());
-      byte[] value = Bytes.toBytes(values[3]);
+      byte[] value = Bytes.toBytes(i.next());
 
       // Create Put
       Put put = new Put(row);
@@ -136,6 +140,7 @@ public class SampleUploader extends Configured implements Tool {
    * @param otherArgs The command line parameters after ToolRunner handles standard.
    * @throws Exception When running the job fails.
    */
+  @Override
   public int run(String[] otherArgs) throws Exception {
     if (otherArgs.length != 2) {
       System.err.println("Wrong number of arguments: " + otherArgs.length);

hbase-examples/src/main/java/org/apache/hadoop/hbase/security/provider/example/ShadeSaslServerAuthenticationProvider.java

@@ -20,6 +20,7 @@ package org.apache.hadoop.hbase.security.provider.example;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
@@ -86,8 +87,8 @@ public class ShadeSaslServerAuthenticationProvider extends ShadeSaslAuthenticati
     }
 
     Map<String, char[]> passwordDb = new HashMap<>();
-    try (FSDataInputStream fdis = fs.open(passwordFile);
+    try (FSDataInputStream fdis = fs.open(passwordFile); BufferedReader reader =
-      BufferedReader reader = new BufferedReader(new InputStreamReader(fdis))) {
+      new BufferedReader(new InputStreamReader(fdis, StandardCharsets.UTF_8))) {
       String line = null;
       int offset = 0;
       while ((line = reader.readLine()) != null) {

hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/DemoClient.java

@@ -41,15 +41,12 @@ import org.apache.thrift.transport.TSaslClientTransport;
 import org.apache.thrift.transport.TSocket;
 import org.apache.thrift.transport.TTransport;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
  * See the instructions under hbase-examples/README.txt
  */
 @InterfaceAudience.Private
 public class DemoClient {
-  private static final Logger LOG = LoggerFactory.getLogger(DemoClient.class);
 
   static protected int port;
   static protected String host;
@@ -128,15 +125,15 @@ public class DemoClient {
     System.out.println("scanning tables...");
 
     for (ByteBuffer name : client.getTableNames()) {
-      System.out.println("  found: " + ClientUtils.utf8(name.array()));
+      System.out.println("  found: " + ClientUtils.utf8(name));
 
       if (name.equals(demoTable) || name.equals(disabledTable)) {
         if (client.isTableEnabled(name)) {
-          System.out.println("    disabling table: " + ClientUtils.utf8(name.array()));
+          System.out.println("    disabling table: " + ClientUtils.utf8(name));
           client.disableTable(name);
         }
 
-        System.out.println("    deleting table: " + ClientUtils.utf8(name.array()));
+        System.out.println("    deleting table: " + ClientUtils.utf8(name));
         client.deleteTable(name);
       }
     }
@@ -324,7 +321,7 @@ public class DemoClient {
     columnNames.clear();
 
     for (ColumnDescriptor col2 : client.getColumnDescriptors(demoTable).values()) {
-      System.out.println("column with name: " + new String(col2.name.array()));
+      System.out.println("column with name: " + ClientUtils.utf8(col2.name));
       System.out.println(col2.toString());
 
       columnNames.add(col2.name);
@@ -356,7 +353,7 @@ public class DemoClient {
       rowStr.append("; ");
     }
 
-    System.out.println("row: " + ClientUtils.utf8(row.array()) + ", values: " + rowStr);
+    System.out.println("row: " + ClientUtils.utf8(row) + ", values: " + rowStr);
   }
 
   private void printRow(TRowResult rowResult) {

hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift/HttpDoAsClient.java

@@ -25,7 +25,6 @@ import java.util.ArrayList;
 import java.util.Base64;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import javax.security.auth.Subject;
@@ -36,8 +35,6 @@ import javax.security.auth.login.LoginContext;
 import org.apache.hadoop.hbase.thrift.generated.AlreadyExists;
 import org.apache.hadoop.hbase.thrift.generated.ColumnDescriptor;
 import org.apache.hadoop.hbase.thrift.generated.Hbase;
-import org.apache.hadoop.hbase.thrift.generated.TCell;
-import org.apache.hadoop.hbase.thrift.generated.TRowResult;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.ClientUtils;
 import org.apache.thrift.protocol.TBinaryProtocol;
@@ -129,13 +126,13 @@ public class HttpDoAsClient {
     //
     System.out.println("scanning tables...");
     for (ByteBuffer name : refresh(client, httpClient).getTableNames()) {
-      System.out.println("  found: " + ClientUtils.utf8(name.array()));
+      System.out.println("  found: " + ClientUtils.utf8(name));
-      if (ClientUtils.utf8(name.array()).equals(ClientUtils.utf8(t))) {
+      if (ClientUtils.utf8(name).equals(ClientUtils.utf8(t))) {
         if (refresh(client, httpClient).isTableEnabled(name)) {
-          System.out.println("    disabling table: " + ClientUtils.utf8(name.array()));
+          System.out.println("    disabling table: " + ClientUtils.utf8(name));
           refresh(client, httpClient).disableTable(name);
         }
-        System.out.println("    deleting table: " + ClientUtils.utf8(name.array()));
+        System.out.println("    deleting table: " + ClientUtils.utf8(name));
         refresh(client, httpClient).deleteTable(name);
       }
     }
@@ -167,8 +164,8 @@ public class HttpDoAsClient {
     Map<ByteBuffer, ColumnDescriptor> columnMap =
       refresh(client, httpClient).getColumnDescriptors(ByteBuffer.wrap(t));
     for (ColumnDescriptor col2 : columnMap.values()) {
-      System.out.println(
+      System.out
-        "  column: " + ClientUtils.utf8(col2.name.array()) + ", maxVer: " + col2.maxVersions);
+        .println("  column: " + ClientUtils.utf8(col2.name) + ", maxVer: " + col2.maxVersions);
     }
 
     transport.close();
@@ -205,26 +202,13 @@ public class HttpDoAsClient {
     context.requestInteg(true);
 
     final byte[] outToken = context.initSecContext(new byte[0], 0, 0);
-    StringBuffer outputBuffer = new StringBuffer();
+    StringBuilder outputBuffer = new StringBuilder();
     outputBuffer.append("Negotiate ");
     outputBuffer.append(Bytes.toString(Base64.getEncoder().encode(outToken)));
     System.out.print("Ticket is: " + outputBuffer);
     return outputBuffer.toString();
   }
 
-  private void printVersions(ByteBuffer row, List<TCell> versions) {
-    StringBuilder rowStr = new StringBuilder();
-    for (TCell cell : versions) {
-      rowStr.append(ClientUtils.utf8(cell.value.array()));
-      rowStr.append("; ");
-    }
-    System.out.println("row: " + ClientUtils.utf8(row.array()) + ", values: " + rowStr);
-  }
-
-  private void printRow(TRowResult rowResult) {
-    ClientUtils.printRow(rowResult);
-  }
-
   static Subject getSubject() throws Exception {
     if (!secure) {
       return new Subject();

hbase-examples/src/main/java/org/apache/hadoop/hbase/thrift2/DemoClient.java

@@ -140,11 +140,11 @@ public class DemoClient {
 
     TResult result = client.get(table, get);
 
-    System.out.print("row = " + new String(result.getRow()));
+    System.out.print("row = " + ClientUtils.utf8(result.getRow()));
     for (TColumnValue resultColumnValue : result.getColumnValues()) {
-      System.out.print("family = " + new String(resultColumnValue.getFamily()));
+      System.out.print("family = " + ClientUtils.utf8(resultColumnValue.getFamily()));
-      System.out.print("qualifier = " + new String(resultColumnValue.getFamily()));
+      System.out.print("qualifier = " + ClientUtils.utf8(resultColumnValue.getFamily()));
-      System.out.print("value = " + new String(resultColumnValue.getValue()));
+      System.out.print("value = " + ClientUtils.utf8(resultColumnValue.getValue()));
       System.out.print("timestamp = " + resultColumnValue.getTimestamp());
     }
 

hbase-examples/src/main/java/org/apache/hadoop/hbase/util/ClientUtils.java

@@ -20,7 +20,6 @@ package org.apache.hadoop.hbase.util;
 import java.nio.ByteBuffer;
 import java.util.HashMap;
 import java.util.Map;
-import java.util.SortedMap;
 import java.util.TreeMap;
 import javax.security.auth.Subject;
 import javax.security.auth.login.AppConfigurationEntry;
@@ -87,7 +86,7 @@ public final class ClientUtils {
     }
 
     StringBuilder rowStr = new StringBuilder();
-    for (SortedMap.Entry<String, TCell> entry : sorted.entrySet()) {
+    for (Map.Entry<String, TCell> entry : sorted.entrySet()) {
       rowStr.append(entry.getKey());
       rowStr.append(" => ");
       rowStr.append(utf8(entry.getValue().value.array()));
@@ -98,8 +97,8 @@ public final class ClientUtils {
   }
 
   /**
-   * Helper to translate byte[]'s to UTF8 strings
+   * Helper to translate byte[]s to UTF8 strings
-   * @param buf byte array buffer
+   * @param buf byte array
    * @return UTF8 decoded string value
    */
   public static String utf8(final byte[] buf) {
@@ -110,4 +109,17 @@ public final class ClientUtils {
     }
   }
 
+  /**
+   * Helper to translate a byte buffer to UTF8 strings
+   * @param bb byte buffer
+   * @return UTF8 decoded string value
+   */
+  public static String utf8(final ByteBuffer bb) {
+    // performance is not very critical here so we always copy the BB to a byte array
+    byte[] buf = new byte[bb.remaining()];
+    // duplicate so the get will not change the position of the original bb
+    bb.duplicate().get(buf);
+    return utf8(buf);
+  }
+
 }

hbase-examples/src/test/java/org/apache/hadoop/hbase/coprocessor/example/WriteHeavyIncrementObserverTestBase.java

@@ -20,6 +20,7 @@ package org.apache.hadoop.hbase.coprocessor.example;
 import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
+import java.io.InterruptedIOException;
 import java.io.UncheckedIOException;
 import java.util.stream.IntStream;
 import org.apache.hadoop.hbase.HBaseTestingUtil;
@@ -78,6 +79,7 @@ public class WriteHeavyIncrementObserverTestBase {
         try {
           Thread.sleep(10);
         } catch (InterruptedException e) {
+          throw (IOException) new InterruptedIOException().initCause(e);
         }
       }
     }

hbase-examples/src/test/java/org/apache/hadoop/hbase/security/provider/example/TestShadeSaslAuthenticationProvider.java

@@ -29,6 +29,7 @@ import java.io.IOException;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.io.StringWriter;
+import java.nio.charset.StandardCharsets;
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -128,8 +129,8 @@ public class TestShadeSaslAuthenticationProvider {
     if (fs.exists(p)) {
       fs.delete(p, true);
     }
-    try (FSDataOutputStream out = fs.create(p);
+    try (FSDataOutputStream out = fs.create(p); BufferedWriter writer =
-      BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out))) {
+      new BufferedWriter(new OutputStreamWriter(out, StandardCharsets.UTF_8))) {
       for (Entry<String, char[]> e : userDatabase.entrySet()) {
         writer.write(e.getKey());
         writer.write(ShadeSaslServerAuthenticationProvider.SEPARATOR);