[ji] adjust Java nio Buffer's inspect

kares · kares · commit a7fe39cb8e63 · 2020-12-17T19:02:22.000+01:00
mostly to have consistent output with all Buffer sub-types
since CharBuffer implements CharSequence -&gt; prints content
(we do not want that for a buffer)

also added Buffer#length/size for convenience
diff --git a/core/src/main/java/org/jruby/javasupport/Java.java b/core/src/main/java/org/jruby/javasupport/Java.java
@@ -116,6 +116,7 @@ public void load(Ruby runtime, boolean wrap) {
         org.jruby.javasupport.ext.JavaUtil.define(runtime);
         org.jruby.javasupport.ext.JavaUtilRegex.define(runtime);
         org.jruby.javasupport.ext.JavaIo.define(runtime);
+        org.jruby.javasupport.ext.JavaNio.define(runtime);
         org.jruby.javasupport.ext.JavaNet.define(runtime);
         org.jruby.javasupport.ext.JavaMath.define(runtime);
         org.jruby.javasupport.ext.JavaTime.define(runtime);
diff --git a/core/src/main/java/org/jruby/javasupport/ext/JavaNio.java b/core/src/main/java/org/jruby/javasupport/ext/JavaNio.java
@@ -0,0 +1,96 @@
+/***** BEGIN LICENSE BLOCK *****
+ * Version: EPL 2.0/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Eclipse Public
+ * License Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.eclipse.org/legal/epl-v20.html
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * Copyright (C) 2020 The JRuby Team
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
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+ * use your version of this file under the terms of the EPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the EPL, the GPL or the LGPL.
+ ***** END LICENSE BLOCK *****/
+
+package org.jruby.javasupport.ext;
+
+import org.jruby.Ruby;
+import org.jruby.RubyClass;
+import org.jruby.RubyModule;
+import org.jruby.RubyString;
+import org.jruby.anno.JRubyMethod;
+import org.jruby.anno.JRubyModule;
+import org.jruby.internal.runtime.methods.JavaMethod;
+import org.jruby.runtime.ThreadContext;
+import org.jruby.runtime.builtin.IRubyObject;
+import org.jruby.util.RubyStringBuilder;
+
+import static org.jruby.javasupport.JavaUtil.unwrapIfJavaObject;
+import static org.jruby.runtime.Visibility.PUBLIC;
+import static org.jruby.util.Inspector.GT;
+import static org.jruby.util.Inspector.SPACE;
+import static org.jruby.util.Inspector.inspectPrefix;
+
+/**
+ * <code>java.nio</code> package additions.
+ *
+ * @author kares
+ */
+public abstract class JavaNio {
+
+    public static void define(final Ruby runtime) {
+        JavaExtensions.put(runtime, java.nio.Buffer.class, (proxy) -> Buffer.define(runtime, (RubyClass) proxy));
+        // make sure it does not use CharSequence#inspect but rather a unified Buffer#inspect format:
+        JavaExtensions.put(runtime, java.nio.CharBuffer.class, (proxy) -> proxy.addMethod("inspect", new InspectBuffer(proxy)));
+    }
+
+    @JRubyModule(name = "Java::JavaNio::Buffer")
+    public static class Buffer {
+
+        static RubyModule define(final Ruby runtime, final RubyClass proxy) {
+            proxy.defineAnnotatedMethods(Buffer.class);
+            proxy.addMethod("inspect", new InspectBuffer(proxy));
+            return proxy;
+        }
+
+        @JRubyMethod(name = {"length", "size"})
+        public static IRubyObject length(final ThreadContext context, final IRubyObject self) {
+            java.nio.Buffer obj = self.toJava(java.nio.Buffer.class);
+            return context.runtime.newFixnum(obj.remaining()); // limit - position
+        }
+
+    }
+
+    private static final class InspectBuffer extends JavaMethod.JavaMethodZero {
+
+        InspectBuffer(RubyModule implClass) {
+            super(implClass, PUBLIC, "inspect");
+        }
+
+        @Override
+        public IRubyObject call(final ThreadContext context, final IRubyObject self, final RubyModule clazz, final java.lang.String name) {
+            java.nio.Buffer obj = unwrapIfJavaObject(self);
+
+            RubyString buf = inspectPrefix(context, self.getMetaClass(), System.identityHashCode(obj));
+            RubyStringBuilder.cat(context.runtime, buf, SPACE);
+            buf.catString("position=" + obj.position() + ", limit=" + obj.limit() + ", capacity=" + obj.capacity() + ", readOnly=" + obj.isReadOnly());
+            RubyStringBuilder.cat(context.runtime, buf, GT); // >
+            return buf;
+        }
+    }
+
+}
diff --git a/spec/java_integration/types/inspect_spec.rb b/spec/java_integration/types/inspect_spec.rb
@@ -30,3 +30,19 @@
     expect(str.inspect).to eq '#<Java::JavaLang::StringBuilder: "bar">'
   end
 end
+
+describe "java.nio.CharSequence" do # implements CharSequence
+  it "inspects as other Buffer impls" do
+    buf = java.nio.CharBuffer.allocate(12)
+    buf.append('a'); buf.put('b')
+    expect(buf.inspect).to match /#<Java::JavaNio::HeapCharBuffer:.*? position=2, limit=12, capacity=12, readOnly=false>/
+  end
+end
+
+describe "java.nio.ByteBuffer" do
+  it "inspects as other Buffer impls" do
+    buf = java.nio.ByteBuffer.allocateDirect(8)
+    buf.put(1)
+    expect(buf.inspect).to match /#<Java::JavaNio::DirectByteBuffer:.*? position=1, limit=8, capacity=8, readOnly=false>/
+  end
+end
