HBASE-23661 Reduced number of Checkstyle violations in hbase-rest

Signed-off-by: Viraj Jasani <vjasani@apache.org>

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/ResultGenerator.java

@@ -16,17 +16,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest;
 
 import java.io.IOException;
 import java.util.Iterator;
 
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.filter.Filter;
 import org.apache.hadoop.hbase.rest.model.ScannerModel;
 
+import org.apache.yetus.audience.InterfaceAudience;
+
 @InterfaceAudience.Private
 public abstract class ResultGenerator implements Iterator<Cell> {
 

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/RowResultGenerator.java

@@ -16,7 +16,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest;
 
 import java.io.IOException;
@@ -26,13 +25,16 @@ import java.util.NoSuchElementException;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.CellUtil;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
-import org.apache.hadoop.hbase.security.AccessDeniedException;
 import org.apache.hadoop.hbase.client.Get;
 import org.apache.hadoop.hbase.client.Result;
 import org.apache.hadoop.hbase.client.Table;
 import org.apache.hadoop.hbase.filter.Filter;
+import org.apache.hadoop.hbase.security.AccessDeniedException;
+
 import org.apache.hadoop.util.StringUtils;
+
 import org.apache.yetus.audience.InterfaceAudience;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -46,8 +48,7 @@ public class RowResultGenerator extends ResultGenerator {
   public RowResultGenerator(final String tableName, final RowSpec rowspec,
       final Filter filter, final boolean cacheBlocks)
       throws IllegalArgumentException, IOException {
-    Table table = RESTServlet.getInstance().getTable(tableName);
-    try {
+    try (Table table = RESTServlet.getInstance().getTable(tableName)) {
       Get get = new Get(rowspec.getRow());
       if (rowspec.hasColumns()) {
         for (byte[] col : rowspec.getColumns()) {
@@ -83,8 +84,6 @@ public class RowResultGenerator extends ResultGenerator {
       if (e instanceof AccessDeniedException) {
         throw e;
       }
-    } finally {
-      table.close();
     }
   }
 

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/client/Response.java

@@ -16,18 +16,19 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.client;
 
 import java.io.IOException;
 import java.io.InputStream;
 
-import org.apache.yetus.audience.InterfaceAudience;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.apache.http.Header;
 import org.apache.http.HttpResponse;
 
+import org.apache.yetus.audience.InterfaceAudience;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 /**
  * The HTTP result code, response headers, and body of an HTTP response.
  */
@@ -71,12 +72,12 @@ public class Response {
   }
   
   /**
-   * Constructor
+   * Constructor. Note: this is not thread-safe
+   *
    * @param code the HTTP response code
    * @param headers headers the HTTP response headers
    * @param resp the response
    * @param in Inputstream if the response had one.
-   * Note: this is not thread-safe
    */
   public Response(int code, Header[] headers, HttpResponse resp, InputStream in) {
     this.code = code;

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/filter/GZIPRequestStream.java

@@ -16,7 +16,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.filter;
 
 import java.io.IOException;
@@ -29,8 +28,7 @@ import javax.servlet.http.HttpServletRequest;
 import org.apache.yetus.audience.InterfaceAudience;
 
 @InterfaceAudience.Private
-public class GZIPRequestStream extends ServletInputStream
-{
+public class GZIPRequestStream extends ServletInputStream {
   private GZIPInputStream in;
 
   public GZIPRequestStream(HttpServletRequest request) throws IOException {

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/filter/GZIPResponseStream.java

@@ -16,7 +16,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.filter;
 
 import java.io.IOException;
@@ -29,8 +28,7 @@ import javax.servlet.http.HttpServletResponse;
 import org.apache.yetus.audience.InterfaceAudience;
 
 @InterfaceAudience.Private
-public class GZIPResponseStream extends ServletOutputStream
-{
+public class GZIPResponseStream extends ServletOutputStream {
   private HttpServletResponse response;
   private GZIPOutputStream out;
 

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/filter/GzipFilter.java

@@ -16,7 +16,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.filter;
 
 import java.io.IOException;
@@ -35,15 +34,16 @@ import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 
+import org.apache.yetus.audience.InterfaceAudience;
+
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
 public class GzipFilter implements Filter {
   private Set<String> mimeTypes = new HashSet<>();
 
   @Override
-  public void init(FilterConfig filterConfig) throws ServletException {
+  public void init(FilterConfig filterConfig) {
     String s = filterConfig.getInitParameter("mimeTypes");
     if (s != null) {
       StringTokenizer tok = new StringTokenizer(s, ",", false);
@@ -66,11 +66,11 @@ public class GzipFilter implements Filter {
     String acceptEncoding = request.getHeader("accept-encoding");
     String contentType = request.getHeader("content-type");
     if ((contentEncoding != null) &&
-        (contentEncoding.toLowerCase(Locale.ROOT).indexOf("gzip") > -1)) {
+        (contentEncoding.toLowerCase(Locale.ROOT).contains("gzip"))) {
       request = new GZIPRequestWrapper(request);
     }
     if (((acceptEncoding != null) &&
-          (acceptEncoding.toLowerCase(Locale.ROOT).indexOf("gzip") > -1)) ||
+          (acceptEncoding.toLowerCase(Locale.ROOT).contains("gzip"))) ||
         ((contentType != null) && mimeTypes.contains(contentType))) {
       response = new GZIPResponseWrapper(response);
     }
@@ -82,5 +82,4 @@ public class GzipFilter implements Filter {
       }
     }
   }
-
 }

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/filter/RestCsrfPreventionFilter.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hbase.rest.filter;
 
 import java.io.IOException;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
@@ -34,10 +35,12 @@ import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.apache.hadoop.conf.Configuration;
+
 import org.apache.yetus.audience.InterfaceAudience;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.apache.hadoop.conf.Configuration;
 
 /**
  * This filter provides protection against cross site request forgery (CSRF)
@@ -48,7 +51,6 @@ import org.apache.hadoop.conf.Configuration;
  */
 @InterfaceAudience.Public
 public class RestCsrfPreventionFilter implements Filter {
-
   private static final Logger LOG =
       LoggerFactory.getLogger(RestCsrfPreventionFilter.class);
 
@@ -66,7 +68,7 @@ public class RestCsrfPreventionFilter implements Filter {
   private Set<Pattern> browserUserAgents;
 
   @Override
-  public void init(FilterConfig filterConfig) throws ServletException {
+  public void init(FilterConfig filterConfig) {
     String customHeader = filterConfig.getInitParameter(CUSTOM_HEADER_PARAM);
     if (customHeader != null) {
       headerName = customHeader;
@@ -100,9 +102,7 @@ public class RestCsrfPreventionFilter implements Filter {
   void parseMethodsToIgnore(String mti) {
     String[] methods = mti.split(",");
     methodsToIgnore = new HashSet<>();
-    for (int i = 0; i < methods.length; i++) {
-      methodsToIgnore.add(methods[i]);
-    }
+    Collections.addAll(methodsToIgnore, methods);
   }
 
   /**
@@ -143,7 +143,6 @@ public class RestCsrfPreventionFilter implements Filter {
    * container configuration mechanisms to insert the filter.
    */
   public interface HttpInteraction {
-
     /**
      * Returns the value of a header.
      *
@@ -223,8 +222,7 @@ public class RestCsrfPreventionFilter implements Filter {
    * @return mapping of configuration properties to be used for filter
    *     initialization
    */
-  public static Map<String, String> getFilterParams(Configuration conf,
-      String confPrefix) {
+  public static Map<String, String> getFilterParams(Configuration conf, String confPrefix) {
     Map<String, String> filterConfigMap = new HashMap<>();
     for (Map.Entry<String, String> entry : conf) {
       String name = entry.getKey();
@@ -240,9 +238,7 @@ public class RestCsrfPreventionFilter implements Filter {
   /**
    * {@link HttpInteraction} implementation for use in the servlet filter.
    */
-  private static final class ServletFilterHttpInteraction
-      implements HttpInteraction {
-
+  private static final class ServletFilterHttpInteraction implements HttpInteraction {
     private final FilterChain chain;
     private final HttpServletRequest httpRequest;
     private final HttpServletResponse httpResponse;

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/CellSetModel.java

@@ -16,7 +16,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.model;
 
 import java.io.IOException;
@@ -29,13 +28,14 @@ import javax.xml.bind.annotation.XmlAccessorType;
 import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
 
-import org.apache.hadoop.hbase.util.ByteStringer;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
 import org.apache.hadoop.hbase.rest.protobuf.generated.CellMessage.Cell;
 import org.apache.hadoop.hbase.rest.protobuf.generated.CellSetMessage.CellSet;
+import org.apache.hadoop.hbase.util.ByteStringer;
+
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * Representation of a grouping of cells. May contain cells from more than
@@ -74,7 +74,6 @@ import org.apache.hadoop.hbase.rest.protobuf.generated.CellSetMessage.CellSet;
 @XmlAccessorType(XmlAccessType.FIELD)
 @InterfaceAudience.Private
 public class CellSetModel implements Serializable, ProtobufMessageHandler {
-
   private static final long serialVersionUID = 1L;
 
   @XmlElement(name="Row")

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/StorageClusterStatusModel.java

@@ -16,9 +16,10 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.model;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import java.io.IOException;
 import java.io.Serializable;
 import java.util.ArrayList;
@@ -29,14 +30,13 @@ import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlElementWrapper;
 import javax.xml.bind.annotation.XmlRootElement;
 
-import org.apache.hadoop.hbase.util.ByteStringer;
-import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
 import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
+import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
 import org.apache.hadoop.hbase.rest.protobuf.generated.StorageClusterStatusMessage.StorageClusterStatus;
+import org.apache.hadoop.hbase.util.ByteStringer;
 import org.apache.hadoop.hbase.util.Bytes;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * Representation of the status of a storage cluster:
@@ -96,8 +96,7 @@ import com.fasterxml.jackson.annotation.JsonProperty;
  */
 @XmlRootElement(name="ClusterStatus")
 @InterfaceAudience.Private
-public class StorageClusterStatusModel
-    implements Serializable, ProtobufMessageHandler {
+public class StorageClusterStatusModel implements Serializable, ProtobufMessageHandler {
   private static final long serialVersionUID = 1L;
 
   /**
@@ -499,8 +498,7 @@ public class StorageClusterStatusModel
     }
 
     /**
-     * @param requests the number of requests per second processed by the
-     * region server
+     * @param requests the number of requests per second processed by the region server
      */
     public void setRequests(long requests) {
       this.requests = requests;
@@ -589,8 +587,8 @@ public class StorageClusterStatusModel
   }
 
   /**
-   * @return the total number of requests per second handled by the cluster in
-   * the last reporting interval
+   * @return the total number of requests per second handled by the cluster in the last reporting
+   *    interval
    */
   @XmlAttribute
   public long getRequests() {
@@ -627,8 +625,7 @@ public class StorageClusterStatusModel
   }
 
   /**
-   * @param requests the total number of requests per second handled by the
-   * cluster
+   * @param requests the total number of requests per second handled by the cluster
    */
   public void setRequests(long requests) {
     this.requests = requests;
@@ -641,10 +638,6 @@ public class StorageClusterStatusModel
     this.averageLoad = averageLoad;
   }
 
-  /*
-   * (non-Javadoc)
-   * @see java.lang.Object#toString()
-   */
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder();
@@ -754,8 +747,7 @@ public class StorageClusterStatusModel
   }
 
   @Override
-  public ProtobufMessageHandler getObjectFromMessage(byte[] message)
-      throws IOException {
+  public ProtobufMessageHandler getObjectFromMessage(byte[] message) throws IOException {
     StorageClusterStatus.Builder builder = StorageClusterStatus.newBuilder();
     ProtobufUtil.mergeFrom(builder, message);
     if (builder.hasRegions()) {

hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/model/TableSchemaModel.java

@@ -16,14 +16,17 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.apache.hadoop.hbase.rest.model;
 
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import com.fasterxml.jackson.annotation.JsonAnySetter;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+
 import java.io.IOException;
 import java.io.Serializable;
 import java.util.ArrayList;
-import java.util.LinkedHashMap;
 import java.util.Iterator;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
@@ -33,20 +36,16 @@ import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.namespace.QName;
 
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.HColumnDescriptor;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HTableDescriptor;
 import org.apache.hadoop.hbase.TableName;
-import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
 import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
+import org.apache.hadoop.hbase.rest.ProtobufMessageHandler;
 import org.apache.hadoop.hbase.rest.protobuf.generated.ColumnSchemaMessage.ColumnSchema;
 import org.apache.hadoop.hbase.rest.protobuf.generated.TableSchemaMessage.TableSchema;
 import org.apache.hadoop.hbase.util.Bytes;
-
-import com.fasterxml.jackson.annotation.JsonAnyGetter;
-import com.fasterxml.jackson.annotation.JsonAnySetter;
-import com.fasterxml.jackson.annotation.JsonIgnore;
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * A representation of HBase table descriptors.
@@ -89,8 +88,7 @@ public class TableSchemaModel implements Serializable, ProtobufMessageHandler {
    */
   public TableSchemaModel(HTableDescriptor htd) {
     setName(htd.getTableName().getNameAsString());
-    for (Map.Entry<Bytes, Bytes> e:
-        htd.getValues().entrySet()) {
+    for (Map.Entry<Bytes, Bytes> e : htd.getValues().entrySet()) {
       addAttribute(Bytes.toString(e.getKey().get()),
         Bytes.toString(e.getValue().get()));
     }
@@ -223,7 +221,7 @@ public class TableSchemaModel implements Serializable, ProtobufMessageHandler {
    */
   public boolean __getIsMeta() {
     Object o = attrs.get(IS_META);
-    return o != null ? Boolean.parseBoolean(o.toString()) : false;
+    return o != null && Boolean.parseBoolean(o.toString());
   }
 
   /**
@@ -231,7 +229,7 @@ public class TableSchemaModel implements Serializable, ProtobufMessageHandler {
    */
   public boolean __getIsRoot() {
     Object o = attrs.get(IS_ROOT);
-    return o != null ? Boolean.parseBoolean(o.toString()) : false;
+    return o != null && Boolean.parseBoolean(o.toString());
   }
 
   /**
@@ -354,5 +352,4 @@ public class TableSchemaModel implements Serializable, ProtobufMessageHandler {
     }
     return htd;
   }
-
 }