Decrease visibility of public constructor in non-public classes. #1555

Fixes `PublicConstructorInNonPublicClass` inspection violations.

Description:
>Reports all constructors in non-public classes that are declared public.

src/main/java/com/puppycrawl/tools/checkstyle/ConfigurationLoader.java

@@ -424,7 +424,7 @@ public final class ConfigurationLoader {
          * @throws SAXException if an error occurs
          * @throws ParserConfigurationException if an error occurs
          */
-        public InternalLoader()
+        InternalLoader()
             throws SAXException, ParserConfigurationException {
             super(createIdToResourceNameMap());
         }

src/main/java/com/puppycrawl/tools/checkstyle/PackageObjectFactory.java

@@ -49,7 +49,7 @@ class PackageObjectFactory implements ModuleFactory {
      * @param moduleClassLoader class loader used to load Checkstyle
      *          core and custom modules
      */
-    public PackageObjectFactory(Set<String> packageNames,
+    PackageObjectFactory(Set<String> packageNames,
             ClassLoader moduleClassLoader) {
         if (moduleClassLoader == null) {
             throw new IllegalArgumentException(

src/main/java/com/puppycrawl/tools/checkstyle/checks/AbstractDeclarationCollector.java

@@ -323,7 +323,7 @@ public abstract class AbstractDeclarationCollector extends Check {
          * Creates new instance of ClassFrame
          * @param parent parent frame
          */
-        public ClassFrame(LexicalFrame parent) {
+        ClassFrame(LexicalFrame parent) {
             super(parent);
             instanceMembers = Sets.newHashSet();
             instanceMethods = Sets.newHashSet();

src/main/java/com/puppycrawl/tools/checkstyle/checks/AbstractTypeAwareCheck.java

@@ -429,7 +429,7 @@ public abstract class AbstractTypeAwareCheck extends Check {
          * @param surroundingClass name of current surrounding class.
          * @param check the check we use to load class.
          */
-        public RegularClass(final Token name,
+        RegularClass(final Token name,
                              final String surroundingClass,
                              final AbstractTypeAwareCheck check) {
             super(name);

src/main/java/com/puppycrawl/tools/checkstyle/checks/SuppressWarningsHolder.java

@@ -449,7 +449,7 @@ public class SuppressWarningsHolder
          * @param lastLine the last line of the suppression region
          * @param lastColumn the last column of the suppression region
          */
-        public Entry(String checkName, int firstLine, int firstColumn,
+        Entry(String checkName, int firstLine, int firstColumn,
             int lastLine, int lastColumn) {
             this.checkName = checkName;
             this.firstLine = firstLine;

src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/AbstractSuperCheck.java

@@ -204,7 +204,7 @@ public abstract class AbstractSuperCheck
          * Constructs a stack node for a method definition.
          * @param ast AST for the method definition.
          */
-        public MethodNode(DetailAST ast) {
+        MethodNode(DetailAST ast) {
             method = ast;
             callingSuper = false;
         }

src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/HiddenFieldCheck.java

@@ -543,7 +543,7 @@ public class HiddenFieldCheck
          * @param staticType is this a static inner type (class or enum).
          * @param frameName name associated with the frame, which can be a
          */
-        public FieldFrame(FieldFrame parent, boolean staticType, String frameName) {
+        FieldFrame(FieldFrame parent, boolean staticType, String frameName) {
             this.parent = parent;
             this.staticType = staticType;
             this.frameName = frameName;

src/main/java/com/puppycrawl/tools/checkstyle/checks/coding/ReturnCountCheck.java

@@ -187,7 +187,7 @@ public final class ReturnCountCheck extends AbstractFormatCheck {
          * Creates new method context.
          * @param checking should we check this method or not.
          */
-        public Context(boolean checking) {
+        Context(boolean checking) {
             this.checking = checking;
             count = 0;
         }

src/main/java/com/puppycrawl/tools/checkstyle/checks/javadoc/AbstractJavadocCheck.java

@@ -646,7 +646,7 @@ public abstract class AbstractJavadocCheck extends Check {
          * @param messageKey message key
          * @param messageArguments message arguments
          */
-        public ParseErrorMessage(int lineNumber, String messageKey, Object ... messageArguments) {
+        ParseErrorMessage(int lineNumber, String messageKey, Object ... messageArguments) {
             this.lineNumber = lineNumber;
             this.messageKey = messageKey;
             this.messageArguments = messageArguments.clone();

src/main/java/com/puppycrawl/tools/checkstyle/checks/metrics/AbstractClassCouplingCheck.java

@@ -210,7 +210,7 @@ public abstract class AbstractClassCouplingCheck extends Check {
          * @param lineNo line of class definition.
          * @param columnNo column of class definition.
          */
-        public Context(String className, int lineNo, int columnNo) {
+        Context(String className, int lineNo, int columnNo) {
             this.className = className;
             this.lineNo = lineNo;
             this.columnNo = columnNo;

src/main/java/com/puppycrawl/tools/checkstyle/checks/metrics/BooleanExpressionComplexityCheck.java

@@ -229,7 +229,7 @@ public final class BooleanExpressionComplexityCheck extends Check {
          * Creates new instance.
          * @param checking should we check in current context or not.
          */
-        public Context(boolean checking) {
+        Context(boolean checking) {
             this.checking = checking;
             count = 0;
         }

src/main/java/com/puppycrawl/tools/checkstyle/checks/sizes/ExecutableStatementCountCheck.java

@@ -203,7 +203,7 @@ public final class ExecutableStatementCountCheck
          * Creates new member context.
          * @param ast member AST node.
          */
-        public Context(DetailAST ast) {
+        Context(DetailAST ast) {
             this.ast = ast;
             count = 0;
         }

src/main/java/com/puppycrawl/tools/checkstyle/filters/CSVFilter.java

@@ -47,7 +47,7 @@ class CSVFilter implements IntFilter {
      * @throws NumberFormatException if a component substring does not
      * contain a parsable integer.
      */
-    public CSVFilter(String pattern) {
+    CSVFilter(String pattern) {
         final StringTokenizer tokenizer = new StringTokenizer(pattern, ",");
         while (tokenizer.hasMoreTokens()) {
             final String token = tokenizer.nextToken().trim();

src/main/java/com/puppycrawl/tools/checkstyle/filters/IntMatchFilter.java

@@ -31,7 +31,7 @@ class IntMatchFilter implements IntFilter {
      * Constructs a MatchFilter for an int.
      * @param matchValue the matching int.
      */
-    public IntMatchFilter(int matchValue) {
+    IntMatchFilter(int matchValue) {
         this.matchValue = matchValue;
     }
 

src/main/java/com/puppycrawl/tools/checkstyle/filters/IntRangeFilter.java

@@ -38,7 +38,7 @@ class IntRangeFilter implements IntFilter {
      * @param lowerBound the lower bound of the range.
      * @param upperBound the upper bound of the range.
      */
-    public IntRangeFilter(int lowerBound, int upperBound) {
+    IntRangeFilter(int lowerBound, int upperBound) {
         this.lowerBound = lowerBound;
         this.upperBound = upperBound;
     }

src/main/java/com/puppycrawl/tools/checkstyle/gui/FileDrop.java

@@ -245,7 +245,7 @@ class FileDrop {
         private final Border dragBorder;
         private final Listener listener;
 
-        public FileDropTargetListener(Component component, Border dragBorder, Listener listener) {
+        FileDropTargetListener(Component component, Border dragBorder, Listener listener) {
             this.component = component;
             this.dragBorder = dragBorder;
             this.listener = listener;

src/main/java/com/puppycrawl/tools/checkstyle/gui/JTreeTable.java

@@ -195,7 +195,7 @@ public class JTreeTable extends JTable {
         private int visibleRow;
 
         /** Creates a new instance */
-        public TreeTableCellRenderer(TreeModel model) {
+        TreeTableCellRenderer(TreeModel model) {
             super(model);
         }
 

src/main/java/com/puppycrawl/tools/checkstyle/gui/ListToTreeSelectionModelWrapper.java

@@ -44,7 +44,7 @@ class ListToTreeSelectionModelWrapper extends DefaultTreeSelectionModel {
     /**
      * @param jTreeTable TreeTable to perform updates on.
      */
-    public ListToTreeSelectionModelWrapper(JTreeTable jTreeTable) {
+    ListToTreeSelectionModelWrapper(JTreeTable jTreeTable) {
         treeTable = jTreeTable;
         getListSelectionModel().addListSelectionListener(createListSelectionListener());
     }

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

@@ -94,7 +94,7 @@ public final class Main {
         /**
          * Contstructor
          */
-        public FrameShower(JFrame frame) {
+        FrameShower(JFrame frame) {
             this.frame = frame;
         }
 

src/main/java/com/puppycrawl/tools/checkstyle/gui/ParseTreeInfoPanel.java

@@ -223,7 +223,7 @@ public class ParseTreeInfoPanel extends JPanel {
         /**
          * Contstructor
          */
-        public FrameShower(Component parent, final String msg) {
+        FrameShower(Component parent, final String msg) {
             this.parent = parent;
             this.msg = msg;
         }
@@ -258,7 +258,7 @@ public class ParseTreeInfoPanel extends JPanel {
          */
         private static final long serialVersionUID = -1926935338069418119L;
 
-        public FileSelectionAction() {
+        FileSelectionAction() {
             super("Select Java File");
             putValue(Action.MNEMONIC_KEY, KeyEvent.VK_S);
         }
@@ -283,7 +283,7 @@ public class ParseTreeInfoPanel extends JPanel {
          */
         private static final long serialVersionUID = -1021880396046355863L;
 
-        public ReloadAction() {
+        ReloadAction() {
             super("Reload Java File");
             putValue(Action.MNEMONIC_KEY, KeyEvent.VK_R);
         }
@@ -299,7 +299,7 @@ public class ParseTreeInfoPanel extends JPanel {
     private class FileDropListener implements FileDrop.Listener {
         private final JScrollPane scrollPane;
 
-        public FileDropListener(JScrollPane scrollPane) {
+        FileDropListener(JScrollPane scrollPane) {
             this.scrollPane = scrollPane;
         }
 

src/test/java/com/puppycrawl/tools/checkstyle/DebugChecker.java

@@ -8,7 +8,7 @@ package com.puppycrawl.tools.checkstyle;
 import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
 
 class DebugChecker extends Checker {
-    public DebugChecker() {
+    DebugChecker() {
     }
 
     @Override