stub hierarchy: use less memory for storing nested classes

java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubEnter.java

@@ -57,7 +57,11 @@ public class StubEnter {
         members[i++] = member;
       }
     }
-    members = members.length == 0 ? ClassSymbol.EMPTY_ARRAY : Arrays.copyOf(members, i);
+    if (i == 0) return ClassSymbol.EMPTY_ARRAY;
+
+    if (i < members.length) {
+      members = Arrays.copyOf(members, i);
+    }
     Arrays.sort(members, CLASS_SYMBOL_BY_NAME_COMPARATOR);
     return members;
   }
@@ -97,8 +101,9 @@ public class StubEnter {
     if (uncompleted != null) {
       uncompleted.add(classSymbol);
     }
-    ClassSymbol[] members = enter(tree.myDeclarations, info, classSymbol, qname);
-    classSymbol.setMembers(members);
+    if (tree.myDeclarations.length > 0) {
+      classSymbol.setMembers(enter(tree.myDeclarations, info, classSymbol, qname));
+    }
     return classSymbol;
   }
 

java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubResolver.java

@@ -103,35 +103,11 @@ public class StubResolver {
     if (!processed.add(s)) {
       return;
     }
-    findImmediateMemberType(s, name, symbols);
+    processMembers(s.getMembers(), name, symbols, false);
     if (s.isClass())
       findInheritedMemberType((Symbol.ClassSymbol)s, name, symbols, processed);
   }
 
-  private static void findImmediateMemberType(Symbol s, int name, Set<Symbol> symbols) {
-    Symbol.ClassSymbol[] members = s.members();
-    int index = getIndex(name, members);
-    if (index < 0) return;
-
-    // elem
-    Symbol.ClassSymbol member = members[index];
-    symbols.add(member);
-    // on the left
-    int i = index - 1;
-    while (i >= 0 && members[i].myShortName == name) {
-      member = members[i];
-      symbols.add(member);
-      i--;
-    }
-    // on the right
-    i = index + 1;
-    while (i < members.length && members[i].myShortName == name) {
-      member = members[i];
-      symbols.add(member);
-      i++;
-    }
-  }
-
   private void findInheritedMemberType(Symbol.ClassSymbol c, int name, Set<Symbol> symbols, Set<Symbol> processed)
     throws IncompleteHierarchyException {
     for (Symbol.ClassSymbol st : c.getSuperClasses(myConnector))
@@ -204,25 +180,25 @@ public class StubResolver {
           return;
         for (Symbol.ClassSymbol c : cs.getSuperClasses(myConnector))
           importFrom(c);
-        importMember(cs.members(), name, symbols, true);
+        processMembers(cs.getMembers(), name, symbols, true);
       }
     }.importFrom(tsym);
   }
 
-  private static void importMember(Symbol.ClassSymbol[] members, int name, Set<Symbol> symbols, boolean isStatic) {
+  private static void processMembers(Symbol.ClassSymbol[] members, int name, Set<Symbol> symbols, boolean requireStatic) {
     int index = getIndex(name, members);
     if (index < 0) return;
 
     // elem
     Symbol.ClassSymbol member = members[index];
-    if (!isStatic || member.isStatic()) {
+    if (!requireStatic || member.isStatic()) {
       symbols.add(member);
     }
     // on the left
     int i = index - 1;
     while (i >= 0 && members[i].myShortName == name) {
       member = members[i];
-      if (!isStatic || member.isStatic()) {
+      if (!requireStatic || member.isStatic()) {
         symbols.add(member);
       }
       i--;
@@ -231,7 +207,7 @@ public class StubResolver {
     i = index + 1;
     while (i < members.length && members[i].myShortName == name) {
       member = members[i];
-      if (!isStatic || member.isStatic()) {
+      if (!requireStatic || member.isStatic()) {
         symbols.add(member);
       }
       i++;

java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/Symbol.java

@@ -45,7 +45,7 @@ public abstract class Symbol {
     return myShortName;
   }
 
-  public ClassSymbol[] members() {
+  ClassSymbol[] getMembers() {
     return ClassSymbol.EMPTY_ARRAY;
   }
 
@@ -84,7 +84,7 @@ public abstract class Symbol {
 
   /** A class for class symbols
    */
-  public static class ClassSymbol extends Symbol {
+  public static class ClassSymbol extends MemberSymbol {
     private static final int HIERARCHY_INCOMPLETE = 1 << 20;
     private static final int CONNECT_STARTED = 1 << 21;
     public static final ClassSymbol[] EMPTY_ARRAY = new ClassSymbol[0];
@@ -98,7 +98,6 @@ public abstract class Symbol {
      */
     Object mySuperClasses;
     UnitInfo myUnitInfo;
-    private ClassSymbol[] myMembers;
 
     ClassSymbol(StubClassAnchor classAnchor,
                 int flags,
@@ -149,14 +148,6 @@ public abstract class Symbol {
       return BitUtil.isSet(myFlags, IndexTree.COMPILED);
     }
 
-    public ClassSymbol[] members() {
-      return myMembers;
-    }
-
-    public void setMembers(ClassSymbol[] members) {
-      this.myMembers = members;
-    }
-
     void markHierarchyIncomplete() {
       setSupers(Collections.emptySet());
       myFlags = BitUtil.set(myFlags, HIERARCHY_INCOMPLETE, true);
@@ -192,15 +183,27 @@ public abstract class Symbol {
    * Represents methods, fields and other constructs that may contain anonymous or local classes.
    */
   public static class MemberSymbol extends Symbol {
-    private ClassSymbol[] myMembers;
-    public MemberSymbol(Symbol owner) {
+    /**
+     * null when no members, or a single ClassSymbol, or ClassSymbol[]
+     */
+    private Object myMembers = null;
+
+    MemberSymbol(Symbol owner) {
       super(IndexTree.MEMBER, owner, NamesEnumerator.NO_NAME);
     }
-    public ClassSymbol[] members() {
-      return myMembers;
+
+    MemberSymbol(int flags, Symbol owner, int name) {
+      super(flags, owner, name);
     }
-    public void setMembers(ClassSymbol[] members) {
-      this.myMembers = members;
+
+    ClassSymbol[] getMembers() {
+      return myMembers == null ? ClassSymbol.EMPTY_ARRAY :
+             myMembers instanceof ClassSymbol ? new ClassSymbol[]{(ClassSymbol)myMembers} :
+             (ClassSymbol[])myMembers;
+    }
+
+    void setMembers(ClassSymbol[] members) {
+      myMembers = members.length == 0 ? null : members.length == 1 ? members[0] : members;
     }
   }