HBASE-19762 Fixed Checkstyle errors in hbase-http

hbase-checkstyle/src/main/resources/hbase/checkstyle-suppressions.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <!DOCTYPE suppressions PUBLIC
-    "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
-    "https://checkstyle.org/dtds/suppressions_1_2.dtd">
+        "-//Checkstyle//DTD SuppressionFilter Configuration 1.2//EN"
+        "https://checkstyle.org/dtds/suppressions_1_2.dtd">
 <!--
 /**
  * Licensed to the Apache Software Foundation (ASF) under one
@@ -37,6 +37,9 @@
   <suppress checks="VisibilityModifier" files=".*/src/test/.*\.java"/>
   <suppress checks="InterfaceIsTypeCheck" files=".*/src/main/.*\.java"/>
   <suppress checks="EmptyBlockCheck" files="TBoundedThreadPoolServer.java"/>
+  <suppress checks="EmptyBlockCheck" files="TestServletFilter.java"/>
+  <suppress checks="EmptyBlockCheck" files="TestGlobalFilter.java"/>
+  <suppress checks="EmptyBlockCheck" files="TestPathFilter.java"/>
   <suppress checks="EqualsHashCode" files="StartcodeAgnosticServerName.java"/>
   <suppress checks="MethodLength" files="Branch1CoprocessorMethods.java"/>
   <suppress checks="IllegalImport" message="org\.apache\.htrace\.core"/>

hbase-http/pom.xml

@@ -120,6 +120,13 @@
           </systemPropertyVariables>
         </configuration>
       </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-checkstyle-plugin</artifactId>
+        <configuration>
+          <failOnViolation>true</failOnViolation>
+        </configuration>
+      </plugin>
       <plugin>
         <groupId>net.revelc.code</groupId>
         <artifactId>warbucks-maven-plugin</artifactId>

hbase-http/src/main/java/org/apache/hadoop/hbase/http/ClickjackingPreventionFilter.java

@@ -17,39 +17,38 @@
  */
 package org.apache.hadoop.hbase.http;
 
+import java.io.IOException;
+
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletResponse;
-import java.io.IOException;
 
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 
+import org.apache.yetus.audience.InterfaceAudience;
+
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
 public class ClickjackingPreventionFilter implements Filter {
-
-    private FilterConfig filterConfig;
-
-    @Override
-    public void init(FilterConfig filterConfig) throws ServletException {
-        this.filterConfig = filterConfig;
-    }
-
-    @Override
-    public void doFilter(ServletRequest req, ServletResponse res,
-                         FilterChain chain)
-            throws IOException, ServletException {
-        HttpServletResponse httpRes = (HttpServletResponse) res;
-        httpRes.addHeader("X-Frame-Options", filterConfig.getInitParameter("xframeoptions"));
-        chain.doFilter(req, res);
-    }
-
-    @Override
-    public void destroy() {
-    }
-
+  private FilterConfig filterConfig;
+
+  @Override
+  public void init(FilterConfig filterConfig) throws ServletException {
+    this.filterConfig = filterConfig;
+  }
+
+  @Override
+  public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
+        throws IOException, ServletException {
+    HttpServletResponse httpRes = (HttpServletResponse) res;
+    httpRes.addHeader("X-Frame-Options", filterConfig.getInitParameter("xframeoptions"));
+    chain.doFilter(req, res);
+  }
+
+  @Override
+  public void destroy() {
+  }
 }

hbase-http/src/main/java/org/apache/hadoop/hbase/http/HtmlQuoting.java

@@ -44,19 +44,19 @@ public final class HtmlQuoting {
    */
   public static boolean needsQuoting(byte[] data, int off, int len) {
     if (off+len > data.length) {
-        throw new IllegalStateException("off+len=" + off+len + " should be lower"
-                + " than data length=" + data.length);
+      throw new IllegalStateException("off+len=" + off+len + " should be lower"
+              + " than data length=" + data.length);
     }
     for(int i=off; i< off+len; ++i) {
       switch(data[i]) {
-      case '&':
-      case '<':
-      case '>':
-      case '\'':
-      case '"':
-        return true;
-      default:
-        break;
+        case '&':
+        case '<':
+        case '>':
+        case '\'':
+        case '"':
+          return true;
+        default:
+          break;
       }
     }
     return false;
@@ -83,16 +83,28 @@ public static boolean needsQuoting(String str) {
    * @param off the index of the first byte to quote
    * @param len the number of bytes to quote
    */
-  public static void quoteHtmlChars(OutputStream output, byte[] buffer,
-                                    int off, int len) throws IOException {
+  public static void quoteHtmlChars(OutputStream output, byte[] buffer, int off, int len)
+          throws IOException {
     for(int i=off; i < off+len; i++) {
       switch (buffer[i]) {
-      case '&': output.write(ampBytes); break;
-      case '<': output.write(ltBytes); break;
-      case '>': output.write(gtBytes); break;
-      case '\'': output.write(aposBytes); break;
-      case '"': output.write(quotBytes); break;
-      default: output.write(buffer, i, 1);
+        case '&':
+          output.write(ampBytes);
+          break;
+        case '<':
+          output.write(ltBytes);
+          break;
+        case '>':
+          output.write(gtBytes);
+          break;
+        case '\'':
+          output.write(aposBytes);
+          break;
+        case '"':
+          output.write(quotBytes);
+          break;
+        default:
+          output.write(buffer, i, 1);
+          break;
       }
     }
   }
@@ -124,10 +136,8 @@ public static String quoteHtmlChars(String item) {
    * Return an output stream that quotes all of the output.
    * @param out the stream to write the quoted output to
    * @return a new stream that the application show write to
-   * @throws IOException if the underlying output fails
    */
-  public static OutputStream quoteOutputStream(final OutputStream out
-                                               ) throws IOException {
+  public static OutputStream quoteOutputStream(final OutputStream out) {
     return new OutputStream() {
       private byte[] data = new byte[1];
       @Override
@@ -202,9 +212,9 @@ public static String unquoteHtmlChars(String item) {
     return buffer.toString();
   }
 
-  public static void main(String[] args) throws Exception {
+  public static void main(String[] args) {
     if (args.length == 0) {
-        throw new IllegalArgumentException("Please provide some arguments");
+      throw new IllegalArgumentException("Please provide some arguments");
     }
     for(String arg:args) {
       System.out.println("Original: " + arg);

hbase-http/src/main/java/org/apache/hadoop/hbase/http/HttpConfig.java

@@ -17,9 +17,10 @@
  */
 package org.apache.hadoop.hbase.http;
 
+import org.apache.hadoop.conf.Configuration;
+
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
-import org.apache.hadoop.conf.Configuration;
 
 /**
  * Statics to get access to Http related configuration.
@@ -51,7 +52,7 @@ public boolean isHttpsEnabled() {
     }
   }
 
-   public HttpConfig(final Configuration conf) {
+  public HttpConfig(final Configuration conf) {
     boolean sslEnabled = conf.getBoolean(
       ServerConfigurationKeys.HBASE_SSL_ENABLED_KEY,
       ServerConfigurationKeys.HBASE_SSL_ENABLED_DEFAULT);

hbase-http/src/main/java/org/apache/hadoop/hbase/http/HttpRequestLogAppender.java

@@ -17,8 +17,8 @@
  */
 package org.apache.hadoop.hbase.http;
 
-import org.apache.log4j.spi.LoggingEvent;
 import org.apache.log4j.AppenderSkeleton;
+import org.apache.log4j.spi.LoggingEvent;
 import org.apache.yetus.audience.InterfaceAudience;
 
 /**