don't always prefer common methods like Object#equals once they ever were chosen

choosing another method from a subclass now also affects all superclass methods statistics

java/java-impl/src/com/intellij/codeInsight/completion/JavaCompletionStatistician.java

@@ -21,6 +21,10 @@ import com.intellij.codeInsight.lookup.LookupItem;
 import com.intellij.psi.*;
 import com.intellij.psi.statistics.JavaStatisticsManager;
 import com.intellij.psi.statistics.StatisticsInfo;
+import com.intellij.psi.util.InheritanceUtil;
+import com.intellij.util.containers.ContainerUtil;
+
+import java.util.List;
 
 /**
  * @author peter
@@ -48,18 +52,21 @@ public class JavaCompletionStatistician extends CompletionStatistician{
         return new StatisticsInfo(JavaStatisticsManager.getAfterNewKey(expectedType), key2);
       }
 
-      if (o instanceof PsiMethod) {
-        o = RecursionWeigher.findDeepestSuper((PsiMethod)o);
-      }
-      
       PsiClass containingClass = ((PsiMember)o).getContainingClass();
       if (containingClass != null) {
-        if (o instanceof PsiMethod && "getClass".equals(((PsiMethod) o).getName()) &&
-            CommonClassNames.JAVA_LANG_OBJECT.equals(containingClass.getQualifiedName())) {
-          return StatisticsInfo.EMPTY;
+        String context = JavaStatisticsManager.getMemberUseKey2(containingClass);
+
+        if (o instanceof PsiMethod) {
+          String memberValue = JavaStatisticsManager.getMemberUseKey2(RecursionWeigher.findDeepestSuper((PsiMethod)o));
+
+          List<StatisticsInfo> superMethodInfos = ContainerUtil.newArrayList(new StatisticsInfo(context, memberValue));
+          for (PsiClass superClass : InheritanceUtil.getSuperClasses(containingClass)) {
+            superMethodInfos.add(new StatisticsInfo(JavaStatisticsManager.getMemberUseKey2(superClass), memberValue));
+          }
+          return StatisticsInfo.createComposite(superMethodInfos);
         }
 
-        return new StatisticsInfo(JavaStatisticsManager.getMemberUseKey2(containingClass), key2);
+        return new StatisticsInfo(context, key2);
       }
     }
 

java/java-tests/testData/codeInsight/completion/normalSorting/AbandonSameStatsForDifferentQualifiers.java

@@ -0,0 +1,11 @@
+class Foo1 { boolean method1() {} }
+class Foo2 { boolean method2() {} }
+class Foo3 { boolean method3() {} }
+
+public class MyFirstTestClassFoo {
+
+  void foo(Foo1 f1, Foo2 f2, Foo3 f3) {
+    f1.<caret>
+  }
+
+}

java/java-tests/testSrc/com/intellij/codeInsight/completion/NormalCompletionOrderingTest.groovy

@@ -181,6 +181,27 @@ public class NormalCompletionOrderingTest extends CompletionSortingTestCase {
     assertPreferredItems(0, "getComponents", "getComponent");
   }
 
+  public void testAbandonSameStatsForDifferentQualifiers() throws Throwable {
+    invokeCompletion(getTestName(false) + ".java");
+    assertPreferredItems 0, "method1", "equals"
+    myFixture.type('eq\n2);\nf2.')
+
+    myFixture.completeBasic();
+    assertPreferredItems 0, "equals", "method2"
+    myFixture.type('me\n);\n')
+
+    for (i in 0..StatisticsManager.OBLIVION_THRESHOLD) {
+      myFixture.type('f2.')
+      myFixture.completeBasic()
+      assertPreferredItems 0, "method2", "equals"
+      myFixture.type('me\n);\n')
+    }
+
+    myFixture.type('f3.')
+    myFixture.completeBasic()
+    assertPreferredItems 0, "method3", "equals"
+  }
+
   public void testDispreferFinalize() throws Throwable {
     checkPreferredItems(0, "final", "finalize");
   }
@@ -394,6 +415,8 @@ import java.lang.annotation.Target;
   public void testDoNotPreferGetClass() {
     checkPreferredItems 0, 'get', 'getClass'
     incUseCount(lookup, 1)
+    assertPreferredItems 0, 'getClass', 'get'
+    incUseCount(lookup, 1)
     assertPreferredItems 0, 'get', 'getClass'
   }
 

platform/lang-impl/src/com/intellij/codeInsight/completion/StatisticsWeigher.java

@@ -191,14 +191,16 @@ public class StatisticsWeigher extends CompletionWeigher {
   }
 
   public static StatisticsInfo composeStatsWithPrefix(StatisticsInfo info, final String fullPrefix, boolean forWriting) {
-    ArrayList<StatisticsInfo> infos = new ArrayList<StatisticsInfo>(fullPrefix.length() + 3);
-    if (forWriting) {
-      infos.add(info);
+    ArrayList<StatisticsInfo> infos = new ArrayList<StatisticsInfo>((fullPrefix.length() + 3) * info.getConjuncts().size());
+    for (StatisticsInfo conjunct : info.getConjuncts()) {
+      if (forWriting) {
+        infos.add(conjunct);
+      }
+      for (int i = 0; i <= fullPrefix.length(); i++) {
+        infos.add(composeWithPrefix(conjunct, fullPrefix.substring(0, i), forWriting));
+      }
+      infos.add(composeWithPrefix(conjunct, fullPrefix, !forWriting));
     }
-    for (int i = 0; i <= fullPrefix.length(); i++) {
-      infos.add(composeWithPrefix(info, fullPrefix.substring(0, i), forWriting));
-    }
-    infos.add(composeWithPrefix(info, fullPrefix, !forWriting));
     return StatisticsInfo.createComposite(infos);
   }