1 files changed, 119 insertions, 0 deletions
diff --git a/java/src/json/ext/RuntimeInfo.java b/java/src/json/ext/RuntimeInfo.java
new file mode 100644
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+++ b/java/src/json/ext/RuntimeInfo.java
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+/*
+ * This code is copyrighted work by Daniel Luz <dev at mernen dot com>.
+ *
+ * Distributed under the Ruby and GPLv2 licenses; see COPYING and GPL files
+ * for details.
+ */
+package json.ext;
+
+import java.lang.ref.WeakReference;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.WeakHashMap;
+import org.jruby.Ruby;
+import org.jruby.RubyClass;
+import org.jruby.RubyEncoding;
+import org.jruby.RubyModule;
+import org.jruby.runtime.ThreadContext;
+import org.jruby.runtime.builtin.IRubyObject;
+
+
+final class RuntimeInfo {
+    // since the vast majority of cases runs just one runtime,
+    // we optimize for that
+    private static WeakReference<Ruby> runtime1 = new WeakReference<Ruby>(null);
+    private static RuntimeInfo info1;
+    // store remaining runtimes here (does not include runtime1)
+    private static Map<Ruby, RuntimeInfo> runtimes;
+
+    // these fields are filled by the service loaders
+    /** JSON */
+    RubyModule jsonModule;
+    /** JSON::Ext::Generator::GeneratorMethods::String::Extend */
+    RubyModule stringExtendModule;
+    /** JSON::Ext::Generator::State */
+    RubyClass generatorStateClass;
+    /** JSON::SAFE_STATE_PROTOTYPE */
+    GeneratorState safeStatePrototype;
+
+    final RubyEncoding utf8;
+    final RubyEncoding ascii8bit;
+    // other encodings
+    private final Map<String, RubyEncoding> encodings;
+
+    private RuntimeInfo(Ruby runtime) {
+        RubyClass encodingClass = runtime.getEncoding();
+        if (encodingClass == null) { // 1.8 mode
+            utf8 = ascii8bit = null;
+            encodings = null;
+        } else {
+            ThreadContext context = runtime.getCurrentContext();
+
+            utf8 = (RubyEncoding)RubyEncoding.find(context,
+                    encodingClass, runtime.newString("utf-8"));
+            ascii8bit = (RubyEncoding)RubyEncoding.find(context,
+                    encodingClass, runtime.newString("ascii-8bit"));
+            encodings = new HashMap<String, RubyEncoding>();
+        }
+    }
+
+    static RuntimeInfo initRuntime(Ruby runtime) {
+        synchronized (RuntimeInfo.class) {
+            if (runtime1.get() == runtime) {
+                return info1;
+            } else if (runtime1.get() == null) {
+                runtime1 = new WeakReference<Ruby>(runtime);
+                info1 = new RuntimeInfo(runtime);
+                return info1;
+            } else {
+                if (runtimes == null) {
+                    runtimes = new WeakHashMap<Ruby, RuntimeInfo>(1);
+                }
+                RuntimeInfo cache = runtimes.get(runtime);
+                if (cache == null) {
+                    cache = new RuntimeInfo(runtime);
+                    runtimes.put(runtime, cache);
+                }
+                return cache;
+            }
+        }
+    }
+
+    public static RuntimeInfo forRuntime(Ruby runtime) {
+        synchronized (RuntimeInfo.class) {
+            if (runtime1.get() == runtime) return info1;
+            RuntimeInfo cache = null;
+            if (runtimes != null) cache = runtimes.get(runtime);
+            assert cache != null : "Runtime given has not initialized JSON::Ext";
+            return cache;
+        }
+    }
+
+    public boolean encodingsSupported() {
+        return utf8 != null;
+    }
+
+    public RubyEncoding getEncoding(ThreadContext context, String name) {
+        synchronized (encodings) {
+            RubyEncoding encoding = encodings.get(name);
+            if (encoding == null) {
+                Ruby runtime = context.getRuntime();
+                encoding = (RubyEncoding)RubyEncoding.find(context,
+                        runtime.getEncoding(), runtime.newString(name));
+                encodings.put(name, encoding);
+            }
+            return encoding;
+        }
+    }
+
+    public GeneratorState getSafeStatePrototype(ThreadContext context) {
+        if (safeStatePrototype == null) {
+            IRubyObject value = jsonModule.getConstant("SAFE_STATE_PROTOTYPE");
+            if (!(value instanceof GeneratorState)) {
+                throw context.getRuntime().newTypeError(value, generatorStateClass);
+            }
+            safeStatePrototype = (GeneratorState)value;
+        }
+        return safeStatePrototype;
+    }
+}