Fix equals and hashCode in SuppressionFilter and remove toString. #1088

pom.xml

@@ -886,7 +886,7 @@
           <regex><pattern>.*.filters.SuppressElement</pattern><branchRate>82</branchRate><lineRate>88</lineRate></regex>
           <regex><pattern>.*.filters.SuppressionCommentFilter</pattern><branchRate>83</branchRate><lineRate>87</lineRate></regex>
           <regex><pattern>.*.filters.SuppressionCommentFilter\$.*</pattern><branchRate>41</branchRate><lineRate>69</lineRate></regex>
-          <regex><pattern>.*.filters.SuppressionFilter</pattern><branchRate>0</branchRate><lineRate>0</lineRate></regex>
+          <regex><pattern>.*.filters.SuppressionFilter</pattern><branchRate>100</branchRate><lineRate>58</lineRate></regex>
           <regex><pattern>.*.filters.SuppressionsLoader</pattern><branchRate>68</branchRate><lineRate>77</lineRate></regex>
           <regex><pattern>.*.filters.SuppressWithNearbyCommentFilter</pattern><branchRate>76</branchRate><lineRate>89</lineRate></regex>
           <regex><pattern>.*.filters.SuppressWithNearbyCommentFilter\$Tag</pattern><branchRate>88</branchRate><lineRate>78</lineRate></regex>

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

@@ -25,6 +25,8 @@ import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
 import com.puppycrawl.tools.checkstyle.api.Filter;
 import com.puppycrawl.tools.checkstyle.api.FilterSet;
 
+import java.util.Objects;
+
 /**
  * <p>
  * This filter accepts AuditEvents according to file, check, line, and
@@ -55,21 +57,19 @@ public class SuppressionFilter
     }
 
     @Override
-    public String toString() {
-        return filters.toString();
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null || getClass() != obj.getClass()) {
+            return false;
+        }
+        final SuppressionFilter that = (SuppressionFilter) obj;
+        return Objects.equals(filters, that.filters);
     }
 
     @Override
     public int hashCode() {
-        return filters.hashCode();
-    }
-
-    @Override
-    public boolean equals(Object object) {
-        if (object instanceof SuppressionFilter) {
-            final SuppressionFilter other = (SuppressionFilter) object;
-            return this.filters.equals(other.filters);
-        }
-        return false;
+        return Objects.hash(filters);
     }
 }

src/test/java/com/puppycrawl/tools/checkstyle/filters/SuppressionFilterTest.java

@@ -0,0 +1,35 @@
+////////////////////////////////////////////////////////////////////////////////
+// checkstyle: Checks Java source code for adherence to a set of rules.
+// Copyright (C) 2001-2015 the original author or authors.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+////////////////////////////////////////////////////////////////////////////////
+
+package com.puppycrawl.tools.checkstyle.filters;
+
+import nl.jqno.equalsverifier.EqualsVerifier;
+import nl.jqno.equalsverifier.Warning;
+import org.junit.Test;
+
+public class SuppressionFilterTest {
+    @Test
+    public void testEqualsAndHashCode() {
+        EqualsVerifier
+                .forClass(SuppressionFilter.class)
+                .usingGetClass()
+                .suppress(Warning.NONFINAL_FIELDS)
+                .verify();
+    }
+}