Merge

checkstyle_checks.xml

@@ -211,5 +211,6 @@
     <module name="PackageAnnotation"/>
     <module name="SuppressWarnings"/>
     <module name="OuterTypeFilename"/>
+    <module name="HideUtilityClassConstructor"/>
   </module>
 </module>

src/checkstyle/com/puppycrawl/tools/checkstyle/Main.java

@@ -58,6 +58,11 @@ public final class Main
             "Sets the output format. (plain|xml). Defaults to plain");
     }
 
+    /** Stop instances being created. */
+    private Main()
+    {
+    }
+
     /**
      * Loops over the files specified checking them for errors. The exit code
      * is the number of errors found in all the files.

src/checkstyle/com/puppycrawl/tools/checkstyle/checks/design/HideUtilityClassConstructorCheck.java

@@ -31,7 +31,6 @@ import com.puppycrawl.tools.checkstyle.api.DetailAST;
  * </p>
  *
  * @author lkuehne
- * @version $Revision: 1.12 $
  */
 public class HideUtilityClassConstructorCheck extends Check
 {
@@ -44,10 +43,17 @@ public class HideUtilityClassConstructorCheck extends Check
     @Override
     public void visitToken(DetailAST aAST)
     {
+        if (isAbstract(aAST)) {
+            // abstract class could not have private constructor
+            return;
+        }
+
         final DetailAST objBlock = aAST.findFirstToken(TokenTypes.OBJBLOCK);
         DetailAST child = objBlock.getFirstChild();
+        final boolean hasStaticModifier = isStatic(aAST);
         boolean hasMethodOrField = false;
         boolean hasNonStaticMethodOrField = false;
+        boolean hasNonPrivateStaticMethodOrField = false;
         boolean hasDefaultCtor = true;
         boolean hasPublicCtor = false;
 
@@ -67,6 +73,9 @@ public class HideUtilityClassConstructorCheck extends Check
                 if (!isStatic && !isPrivate) {
                     hasNonStaticMethodOrField = true;
                 }
+                if (isStatic && !isPrivate) {
+                    hasNonPrivateStaticMethodOrField = true;
+                }
             }
             if (type == TokenTypes.CTOR_DEF) {
                 hasDefaultCtor = false;
@@ -93,11 +102,31 @@ public class HideUtilityClassConstructorCheck extends Check
         final boolean extendsJLO = // J.Lo even made it into in our sources :-)
             aAST.findFirstToken(TokenTypes.EXTENDS_CLAUSE) == null;
 
-        final boolean isUtilClass =
-            extendsJLO && hasMethodOrField && !hasNonStaticMethodOrField;
+        final boolean isUtilClass = extendsJLO && hasMethodOrField
+            && !hasNonStaticMethodOrField && hasNonPrivateStaticMethodOrField;
 
-        if (isUtilClass && hasAccessibleCtor) {
+        if (isUtilClass && (hasAccessibleCtor && !hasStaticModifier)) {
             log(aAST.getLineNo(), aAST.getColumnNo(), "hide.utility.class");
         }
     }
+
+    /**
+     * @param aAST class definition for check.
+     * @return true if a given class declared as abstract.
+     */
+    private boolean isAbstract(DetailAST aAST)
+    {
+        return aAST.findFirstToken(TokenTypes.MODIFIERS)
+            .branchContains(TokenTypes.ABSTRACT);
+    }
+
+    /**
+     * @param aAST class definition for check.
+     * @return true if a given class declared as static.
+     */
+    private boolean isStatic(DetailAST aAST)
+    {
+        return aAST.findFirstToken(TokenTypes.MODIFIERS)
+            .branchContains(TokenTypes.LITERAL_STATIC);
+    }
 }

src/checkstyle/com/puppycrawl/tools/checkstyle/doclets/CheckDocsDoclet.java

@@ -41,6 +41,11 @@ public final class CheckDocsDoclet
     /** javadoc command line option for dest dir. */
     private static final String DEST_DIR_OPT = "-d";
 
+    /** Stop instances being created. */
+    private CheckDocsDoclet()
+    {
+    }
+
     /**
      * Comparator that compares the {@link ClassDoc ClassDocs} of two checks
      * by their check name.

src/checkstyle/com/puppycrawl/tools/checkstyle/doclets/TokenTypesDoclet.java

@@ -33,11 +33,16 @@ import com.sun.javadoc.RootDoc;
  *
  * @author o_sukhodolsky
  */
-public class TokenTypesDoclet
+public final class TokenTypesDoclet
 {
     /** Command line option to specify file to write output of the doclet. */
     private static final String DEST_FILE_OPT = "-destfile";
 
+    /** Stop instances being created. */
+    private TokenTypesDoclet()
+    {
+    }
+
     /**
      * The doclet's starter method.
      * @param aRoot <code>RootDoc</code> given to the doclet

src/testinputs/com/puppycrawl/tools/checkstyle/design/HideUtilityClassContructor3041574_1.java

@@ -0,0 +1,8 @@
+package com.puppycrawl.tools.checkstyle.design;
+
+import java.io.Serializable;
+
+public abstract class HideUtilityClassContructor3041574_1 implements Serializable {
+    private static final long serialVersionUID = 1L;
+
+}

src/testinputs/com/puppycrawl/tools/checkstyle/design/HideUtilityClassContructor3041574_2.java

@@ -0,0 +1,8 @@
+package com.puppycrawl.tools.checkstyle.design;
+
+import java.io.Serializable;
+
+public class HideUtilityClassContructor3041574_2 implements Serializable {
+    private static final long serialVersionUID = 1L;
+
+}

src/testinputs/com/puppycrawl/tools/checkstyle/design/HideUtilityClassContructor3041574_3.java

@@ -0,0 +1,48 @@
+package com.puppycrawl.tools.checkstyle.design;
+
+import java.io.Serializable;
+
+public class HideUtilityClassContructor3041574_3 implements Serializable {
+    private static final long serialVersionUID = 1L;
+
+    public HideUtilityClassContructor3041574_3(int i) {
+        // no code
+    }
+
+    public String getValue() {
+        return "";
+    }
+    
+    // It is NOT Utility Inner class
+    @SuppressWarnings("unused")
+    public static class Event {
+        // Top level class have access to fields - no need in public getters
+        private String ind;
+        private String ind1;
+        
+        public Event(String value){
+            // do a lot of calculations
+        }
+        
+        // static because this method is utility
+        public static String getEmptyString() {
+            return "";
+        }
+    }
+    
+    // It is Utility Inner class
+    @SuppressWarnings("unused")
+    public static class Event1 {
+        private String ind;
+        private String ind1;
+        
+        private Event1(){
+            // do a lot of calculations
+        }
+        
+        // static because this method is utility
+        public static String getEmptyString() {
+            return "";
+        }
+    }
+}

src/tests/com/puppycrawl/tools/checkstyle/checks/design/HideUtilityClassConstructorCheckTest.java

@@ -69,4 +69,34 @@ public class HideUtilityClassConstructorCheckTest
         verify(checkConfig, getPath("design" + File.separator + "InputRegression1762702.java"), expected);
     }
 
+    @Test
+    public void testEmptyAbstractClass() throws Exception
+    {
+        final DefaultConfiguration checkConfig =
+            createCheckConfig(HideUtilityClassConstructorCheck.class);
+        final String[] expected = {
+        };
+        verify(checkConfig, getPath("design" + File.separator + "HideUtilityClassContructor3041574_1.java"), expected);
+    }
+
+    @Test
+    public void testEmptyClassWithOnlyPrivateFields() throws Exception
+    {
+        final DefaultConfiguration checkConfig =
+            createCheckConfig(HideUtilityClassConstructorCheck.class);
+        final String[] expected = {
+        };
+        verify(checkConfig, getPath("design" + File.separator + "HideUtilityClassContructor3041574_2.java"), expected);
+    }
+
+    @Test
+    public void testClassWithStaticInnerClass() throws Exception
+    {
+        final DefaultConfiguration checkConfig =
+            createCheckConfig(HideUtilityClassConstructorCheck.class);
+        final String[] expected = {
+        };
+        verify(checkConfig, getPath("design" + File.separator + "HideUtilityClassContructor3041574_3.java"), expected);
+    }
+
 }

src/xdocs/config_design.xml

@@ -219,7 +219,8 @@
 public class StringUtils // not final to allow subclassing
 {
     protected StringUtils() {
-        throw new UnsupportedOperationException(); // prevents calls from subclass
+        // prevents calls from subclass
+        throw new UnsupportedOperationException();
     }
 
     public static int count(char c, String s) {

src/xdocs/releasenotes.xml

@@ -72,6 +72,12 @@
           checking of <code>@throws</code> tags for methods that throw multiple
           non-runtime exceptions. Thanks to Daan Kets for patch #3039869.
         </li>
+        <li>
+          Fix
+          <a href="config_design.html#HideUtilityClassConstructor">HideUtilityClassConstructor</a>
+          to handle empty and inner classes. Thanks to Roman Ivanov for
+          patch #3045720.
+        </li>
       </ul>
       <p>Notes:</p>
       <ul>