From 4d048bbc4c20594376fa9e8ab6d63d121d5bfce5 Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Fri, 10 Jun 2016 10:34:02 +0200
Subject: [PATCH] release stub hierarchy name enumerator to save memory;
 reusing it brings almost nothing anyway

---
 .../impl/HierarchyServiceImpl.java            | 30 +++++--------------
 .../psi/stubsHierarchy/impl/StubEnter.java    |  8 ++---
 .../psi/stubsHierarchy/impl/Symbols.java      |  9 +++---
 3 files changed, 15 insertions(+), 32 deletions(-)

diff --git a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/HierarchyServiceImpl.java b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/HierarchyServiceImpl.java
index 159a4f6c1db2..31fa42faa53a 100644
--- a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/HierarchyServiceImpl.java
+++ b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/HierarchyServiceImpl.java
@@ -31,7 +31,6 @@ import com.intellij.psi.util.CachedValue;
 import com.intellij.psi.util.CachedValueProvider;
 import com.intellij.psi.util.CachedValuesManager;
 import com.intellij.psi.util.PsiModificationTracker;
-import com.intellij.reference.SoftReference;
 import com.intellij.util.CachedValueBase;
 import com.intellij.util.indexing.FileBasedIndex;
 import org.jetbrains.annotations.NotNull;
@@ -40,9 +39,7 @@ public class HierarchyServiceImpl extends HierarchyService {
   private static final SingleClassHierarchy EMPTY_HIERARCHY = new SingleClassHierarchy(Symbol.ClassSymbol.EMPTY_ARRAY);
   private final Project myProject;
   private final ProjectFileIndex myFileIndex;
-
-  private volatile SoftReference<NameEnvironment> myNamesCache = null;
-  private final CachedValue<SingleClassHierarchy> myHierarchy ;
+  private final CachedValue<SingleClassHierarchy> myHierarchy;
 
   public HierarchyServiceImpl(Project project) {
     myProject = project;
@@ -70,29 +67,16 @@ public class HierarchyServiceImpl extends HierarchyService {
   }
 
   private SingleClassHierarchy buildHierarchy() {
-    NameEnvironment names = obtainNames();
-    Symbols symbols = new Symbols(names);
-    loadSymbols(names, symbols);
-    return symbols.createHierarchy();
-  }
+    Symbols symbols = new Symbols();
+    StubEnter stubEnter = new StubEnter(symbols);
 
-  @NotNull
-  private NameEnvironment obtainNames() {
-    NameEnvironment names = SoftReference.dereference(myNamesCache);
-    if (names == null) {
-      myNamesCache = new SoftReference<NameEnvironment>(names = new NameEnvironment());
-    }
-    return names;
-  }
-
-  private void loadSymbols(NameEnvironment names, Symbols symbols) {
-    StubEnter stubEnter = new StubEnter(names, symbols);
-
-    loadUnits(false, names, stubEnter);
+    loadUnits(false, symbols.myNameEnvironment, stubEnter);
     stubEnter.connect1();
 
-    loadUnits(true, names, stubEnter);
+    loadUnits(true, symbols.myNameEnvironment, stubEnter);
     stubEnter.connect2();
+
+    return symbols.createHierarchy();
   }
 
   private void loadUnits(boolean sourceMode, NameEnvironment names, StubEnter stubEnter) {
diff --git a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubEnter.java b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubEnter.java
index 42aec9d49b90..728a39f29c21 100644
--- a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubEnter.java
+++ b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/StubEnter.java
@@ -30,10 +30,10 @@ public class StubEnter {
 
   private ArrayList<ClassSymbol> uncompleted = new ArrayList<ClassSymbol>();
 
-  public StubEnter(NameEnvironment nameEnvironment, Symbols symbols) {
-    this.myNameEnvironment = nameEnvironment;
-    this.mySymbols = symbols;
-    myStubHierarchyConnector = new StubHierarchyConnector(nameEnvironment, symbols);
+  StubEnter(Symbols symbols) {
+    myNameEnvironment = symbols.myNameEnvironment;
+    mySymbols = symbols;
+    myStubHierarchyConnector = new StubHierarchyConnector(myNameEnvironment, symbols);
   }
 
   void unitEnter(Unit tree) {
diff --git a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/Symbols.java b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/Symbols.java
index 16ed9f1f2903..42feaf324509 100644
--- a/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/Symbols.java
+++ b/java/java-impl/src/com/intellij/psi/stubsHierarchy/impl/Symbols.java
@@ -12,7 +12,7 @@ import java.util.List;
 
 public class Symbols {
   public final PackageSymbol myRootPackage;
-  protected final NameEnvironment myNameEnvironment;
+  protected final NameEnvironment myNameEnvironment = new NameEnvironment();
 
   private List<ClassSymbol> myClassSymbols = new ArrayList<>(0x8000);
   // fullName -> PackageSymbol
@@ -20,10 +20,9 @@ public class Symbols {
   // nameId -> ClassSymbols (used by global resolve)
   private Object[] myClassSymbolsByNameId = new Object[0x8000];
 
-  protected Symbols(NameEnvironment nameEnvironment) {
-    this.myNameEnvironment = nameEnvironment;
-    myRootPackage = new PackageSymbol(null, nameEnvironment.empty, NamesEnumerator.NO_NAME);
-    myPackages.put(nameEnvironment.empty.myId, myRootPackage);
+  protected Symbols() {
+    myRootPackage = new PackageSymbol(null, myNameEnvironment.empty, NamesEnumerator.NO_NAME);
+    myPackages.put(myNameEnvironment.empty.myId, myRootPackage);
   }
 
   public PackageSymbol enterPackage(QualifiedName qualifiedName) {