Bug 888 - Validate CPU Runtime Performance: Only use one HashMap to collect unified gl- and glx-extension strings.

- HashMap is more efficient than HashSet
- No need to use sub HashSet's .. we can use global HashMap.
  'Loosing' duplicate GLX entries due to GL duplicates is acceptable.

1 files changed, 38 insertions, 30 deletions

diff --git a/src/jogl/classes/jogamp/opengl/ExtensionAvailabilityCache.java b/src/jogl/classes/jogamp/opengl/ExtensionAvailabilityCache.java
index 8d3d207ee..fd59ecfd4 100644
--- a/src/jogl/classes/jogamp/opengl/ExtensionAvailabilityCache.java
+++ b/src/jogl/classes/jogamp/opengl/ExtensionAvailabilityCache.java
@@ -40,11 +40,14 @@
 
 package jogamp.opengl;
 
-import javax.media.opengl.*;
+import java.util.HashMap;
+import java.util.StringTokenizer;
 
-import com.jogamp.common.util.VersionNumber;
+import javax.media.opengl.GL;
+import javax.media.opengl.GL2GL3;
+import javax.media.opengl.GLContext;
 
-import java.util.*;
+import com.jogamp.common.util.VersionNumber;
 
 /**
  * A utility object intended to be used by implementations to act as a cache
@@ -80,7 +83,7 @@ final class ExtensionAvailabilityCache {
   }
 
   final boolean isInitialized() {
-    return initialized && !availableExtensionCache.isEmpty() ;
+    return initialized;
   }
 
   final int getTotalExtensionCount() {
@@ -90,7 +93,7 @@ final class ExtensionAvailabilityCache {
 
   final boolean isExtensionAvailable(String glExtensionName) {
     validateInitialization();
-    return availableExtensionCache.contains(glExtensionName);
+    return null != availableExtensionCache.get(glExtensionName);
   }
 
   final int getPlatformExtensionCount() {
@@ -151,7 +154,6 @@ final class ExtensionAvailabilityCache {
                   ", use "+ ( useGetStringi ? "glGetStringi" : "glGetString" ) );
       }
 
-      HashSet<String> glExtensionSet = new HashSet<String>(gl.isGLES() ? 50 : 320); // far less gl extension expected on mobile
       if(useGetStringi) {
           GL2GL3 gl2gl3 = gl.getGL2GL3();
           final int count;
@@ -162,57 +164,63 @@ final class ExtensionAvailabilityCache {
           }
           StringBuilder sb = new StringBuilder();
           for (int i = 0; i < count; i++) {
-              if(i > 0) {
-                  sb.append(" ");
-              }
               final String ext = gl2gl3.glGetStringi(GL.GL_EXTENSIONS, i);
-              glExtensionSet.add(ext);
-              sb.append(ext);
+              if( null == availableExtensionCache.put(ext, ext) ) {
+                  // new one
+                  if( 0 < i ) {
+                      sb.append(" ");
+                  }
+                  sb.append(ext);
+              }
           }
           if(0==count || sb.length()==0) {
               // fall back ..
               useGetStringi=false;
           } else {
               glExtensions = sb.toString();
+              glExtensionCount = count;
           }
       }
       if(!useGetStringi) {
           glExtensions = gl.glGetString(GL.GL_EXTENSIONS);
           if(null != glExtensions) {
-              StringTokenizer tok = new StringTokenizer(glExtensions);
+              final StringTokenizer tok = new StringTokenizer(glExtensions);
+              int count = 0;
               while (tok.hasMoreTokens()) {
-                  glExtensionSet.add(tok.nextToken().trim());
+                  final String ext = tok.nextToken().trim();
+                  if( null == availableExtensionCache.put(ext, ext) ) {
+                      count++;
+                  }
               }
+              glExtensionCount = count;
           }
       }
-      glExtensionCount = glExtensionSet.size();
       if (DEBUG) {
           System.err.println(getThreadName() + ":ExtensionAvailabilityCache: GL_EXTENSIONS: "+glExtensionCount+
                                                ", used "+ ( useGetStringi ? "glGetStringi" : "glGetString" ) );
       }
 
       // Platform Extensions
-      HashSet<String> glXExtensionSet = new HashSet<String>(50);
       {
           // unify platform extension .. might have duplicates
-          StringTokenizer tok = new StringTokenizer(context.getPlatformExtensionsStringImpl().toString());
-          while (tok.hasMoreTokens()) {
-              glXExtensionSet.add(tok.nextToken().trim());
-          }
           final StringBuilder sb = new StringBuilder();
-          for(Iterator<String> iter = glXExtensionSet.iterator(); iter.hasNext(); ) {
-              sb.append(iter.next());
-              if(iter.hasNext()) {
-                  sb.append(" ");
+          final StringTokenizer tok = new StringTokenizer(context.getPlatformExtensionsStringImpl().toString());
+          int count = 0;
+          while (tok.hasMoreTokens()) {
+              final String ext = tok.nextToken().trim();
+              if( null == availableExtensionCache.put(ext, ext) ) {
+                  // new one
+                  if( 0 < count ) {
+                      sb.append(" ");
+                  }
+                  sb.append(ext);
+                  count++;
               }
           }
           glXExtensions = sb.toString();
-          glXExtensionCount = glXExtensionSet.size();
+          glXExtensionCount = count;
       }
 
-      availableExtensionCache.addAll(glExtensionSet);
-      availableExtensionCache.addAll(glXExtensionSet);
-
       if (DEBUG) {
           System.err.println(getThreadName() + ":ExtensionAvailabilityCache: GLX_EXTENSIONS: "+glXExtensionCount);
           System.err.println(getThreadName() + ":ExtensionAvailabilityCache: GL vendor: " + gl.glGetString(GL.GL_VENDOR));
@@ -225,7 +233,7 @@ final class ExtensionAvailabilityCache {
       int minor[] = new int[] { version.getMinor() };
       do{
           final String GL_XX_VERSION = ( context.isGLES() ? "GL_ES_VERSION_" : "GL_VERSION_" ) + major[0] + "_" + minor[0];
-          availableExtensionCache.add(GL_XX_VERSION);
+          availableExtensionCache.put(GL_XX_VERSION, GL_XX_VERSION);
           if (DEBUG) {
               System.err.println(getThreadName() + ":ExtensionAvailabilityCache: Added "+GL_XX_VERSION+" to known extensions");
           }
@@ -233,7 +241,7 @@ final class ExtensionAvailabilityCache {
 
       // put a dummy var in here so that the cache is no longer empty even if
       // no extensions are in the GL_EXTENSIONS string
-      availableExtensionCache.add("<INTERNAL_DUMMY_PLACEHOLDER>");
+      availableExtensionCache.put("<INTERNAL_DUMMY_PLACEHOLDER>", "<INTERNAL_DUMMY_PLACEHOLDER>");
 
       initialized = true;
   }
@@ -247,7 +255,7 @@ final class ExtensionAvailabilityCache {
   private int glExtensionCount = 0;
   private String glXExtensions = null;
   private int glXExtensionCount = 0;
-  private final HashSet<String> availableExtensionCache = new HashSet<String>(50);
+  private final HashMap<String, String> availableExtensionCache = new HashMap<String, String>(100);
 
   static String getThreadName() { return Thread.currentThread().getName(); }