Merge JRuby-compatible extension into json proper.

1 files changed, 113 insertions, 0 deletions

diff --git a/src/json/ext/OptionsReader.java b/src/json/ext/OptionsReader.java
new file mode 100644
index 0000000..29de188
--- /dev/null
+++ b/src/json/ext/OptionsReader.java
@@ -0,0 +1,113 @@
+/*
+ * 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 org.jruby.Ruby;
+import org.jruby.RubyClass;
+import org.jruby.RubyHash;
+import org.jruby.RubyNumeric;
+import org.jruby.RubyString;
+import org.jruby.runtime.ThreadContext;
+import org.jruby.runtime.builtin.IRubyObject;
+import org.jruby.util.ByteList;
+
+final class OptionsReader {
+    private final ThreadContext context;
+    private final Ruby runtime;
+    private final RuntimeInfo info;
+    private final RubyHash opts;
+
+    private OptionsReader(ThreadContext context, Ruby runtime,
+                          RuntimeInfo info, IRubyObject vOpts) {
+        this.context = context;
+        this.runtime = runtime;
+        this.info = info;
+
+        if (vOpts == null || vOpts.isNil()) {
+            opts = null;
+        } else if (vOpts.respondsTo("to_hash")) {
+            opts = vOpts.convertToHash();
+        } else {
+            opts = vOpts.callMethod(context, "to_h").convertToHash();
+        }
+    }
+
+    OptionsReader(ThreadContext context, IRubyObject vOpts) {
+        this(context, context.getRuntime(), null, vOpts);
+    }
+
+    static OptionsReader withStrings(ThreadContext context, IRubyObject vOpts) {
+        Ruby runtime = context.getRuntime();
+        return new OptionsReader(context, runtime,
+                RuntimeInfo.forRuntime(runtime), vOpts);
+    }
+
+    /**
+     * Efficiently looks up items with a {@link RubySymbol Symbol} key
+     * @param key The Symbol name to look up for
+     * @return The item in the {@link RubyHash Hash}, or <code>null</code>
+     *         if not found
+     */
+    IRubyObject get(String key) {
+        return opts == null ? null : opts.fastARef(runtime.newSymbol(key));
+    }
+
+    boolean getBool(String key, boolean defaultValue) {
+        IRubyObject value = get(key);
+        return value == null ? defaultValue : value.isTrue();
+    }
+
+    int getInt(String key, int defaultValue) {
+        IRubyObject value = get(key);
+        if (value == null) return defaultValue;
+        if (!value.isTrue()) return 0;
+        return RubyNumeric.fix2int(value);
+    }
+
+    /**
+     * Reads the setting from the options hash. If no entry is set for this
+     * key or if it evaluates to <code>false</code>, returns null; attempts to
+     * coerce the value to {@link RubyString String} otherwise.
+     * @param key The Symbol name to look up for
+     * @return <code>null</code> if the key is not in the Hash or if
+     *         its value evaluates to <code>false</code>
+     * @throws RaiseException <code>TypeError</code> if the value does not
+     *                        evaluate to <code>false</code> and can't be
+     *                        converted to string
+     */
+    ByteList getString(String key) {
+        IRubyObject value = get(key);
+        if (value == null || !value.isTrue()) return null;
+
+        RubyString str = value.convertToString();
+        if (info.encodingsSupported() && str.encoding(context) != info.utf8) {
+            str = (RubyString)str.encode(context, info.utf8);
+        }
+        return str.getByteList().dup();
+    }
+
+    /**
+     * Reads the setting from the options hash. If it is <code>nil</code> or
+     * undefined, returns the default value given.
+     * If not, ensures it is a RubyClass instance and shares the same
+     * allocator as the default value (i.e. for the basic types which have
+     * their specific allocators, this ensures the passed value is
+     * a subclass of them).
+     */
+    RubyClass getClass(String key, RubyClass defaultValue) {
+        IRubyObject value = get(key);
+
+        if (value == null || value.isNil()) return defaultValue;
+
+        if (value instanceof RubyClass &&
+                ((RubyClass)value).getAllocator() == defaultValue.getAllocator()) {
+            return (RubyClass)value;
+        }
+        throw runtime.newTypeError(key + " option must be a subclass of "
+                                   + defaultValue);
+    }
+}