Revert "Cache all Charset instances with their aliases"
This reverts commit 363101a5af755ae1d5baa32d79b3d4a97626f6ff.
bug: 26457745
bug: 26140874
Change-Id: Iff3151dfe0e987ea22f795570dbc182e93a00804
diff --git a/ojluni/src/main/java/java/nio/charset/Charset.java b/ojluni/src/main/java/java/nio/charset/Charset.java
index 57bacaa..1313828 100755
--- a/ojluni/src/main/java/java/nio/charset/Charset.java
+++ b/ojluni/src/main/java/java/nio/charset/Charset.java
@@ -34,9 +34,7 @@
import java.security.AccessController;
import java.security.AccessControlException;
import java.security.PrivilegedAction;
-import java.util.AbstractMap;
import java.util.Collections;
-import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Locale;
@@ -332,22 +330,12 @@
// Cache of the most-recently-returned charsets,
// along with the names that were used to find them
//
- // cache1/2 usage is explained in the lookup method
- //
- private static volatile Map.Entry<String, Charset> cache1 = null; // "Level 1" cache
- private static final HashMap<String, Charset> cache2 = new HashMap<>(); // "Level 2" cache
+ private static volatile Object[] cache1 = null; // "Level 1" cache
+ private static volatile Object[] cache2 = null; // "Level 2" cache
private static void cache(String charsetName, Charset cs) {
- synchronized(cache2) {
- String canonicalName = cs.name();
- cache2.put(canonicalName, cs);
-
- for (String alias : cs.aliases()) {
- cache2.put(alias, cs);
- }
- }
-
- cache1 = new AbstractMap.SimpleImmutableEntry<>(charsetName, cache2.get(charsetName));
+ cache2 = cache1;
+ cache1 = new Object[] { charsetName, cs };
}
// Creates an iterator that walks over the available providers, ignoring
@@ -478,29 +466,28 @@
// return (ecp != null) ? ecp.charsetForName(charsetName) : null;
// }
- // We expect most programs to use one Charset repeatedly, so the most recently used Charset
- // instance is stored in the level 1 cache. We convey a hint to this effect to the VM by putting
- // the level 1 cache miss code in a separate method. Since charsetName is not necessarily in
- // canonical form, we store the mapping from both the canonical name and the aliases to the
- // instance in a map for level 2 cache.
private static Charset lookup(String charsetName) {
if (charsetName == null)
throw new IllegalArgumentException("Null charset name");
- if (cache1 != null && charsetName.equals(cache1.getKey()))
- return cache1.getValue();
+ Object[] a;
+ if ((a = cache1) != null && charsetName.equals(a[0]))
+ return (Charset)a[1];
+ // We expect most programs to use one Charset repeatedly.
+ // We convey a hint to this effect to the VM by putting the
+ // level 1 cache miss code in a separate method.
return lookup2(charsetName);
}
private static Charset lookup2(String charsetName) {
- Charset cs;
- synchronized (cache2) {
- if ((cs = cache2.get(charsetName)) != null) {
- cache1 = new AbstractMap.SimpleImmutableEntry<>(charsetName, cs);
- return cs;
- }
+ Object[] a;
+ if ((a = cache2) != null && charsetName.equals(a[0])) {
+ cache2 = cache1;
+ cache1 = a;
+ return (Charset)a[1];
}
+ Charset cs;
// Android-changed: Drop support for "standard" and "extended"
// providers.
if ((cs = NativeConverter.charsetForName(charsetName)) != null ||
