[#1851] EmptyByteBuf.isWritable(..) and isReadable(...) should not throw IndexOutOfBoundsException

buffer/src/main/java/io/netty/buffer/EmptyByteBuf.java

@@ -807,13 +807,11 @@ public final class EmptyByteBuf extends ByteBuf {
 
     @Override
     public boolean isReadable(int size) {
-        checkLength(size);
         return false;
     }
 
     @Override
     public boolean isWritable(int size) {
-        checkLength(size);
         return false;
     }
 

buffer/src/test/java/io/netty/buffer/EmptyByteBufTest.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2013 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache 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.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */package io.netty.buffer;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class EmptyByteBufTest {
+
+    @Test
+    public void testIsWritable() {
+        EmptyByteBuf empty = new EmptyByteBuf(UnpooledByteBufAllocator.DEFAULT);
+        Assert.assertFalse(empty.isWritable());
+        Assert.assertFalse(empty.isWritable(1));
+    }
+
+    @Test
+    public void testIsReadable() {
+        EmptyByteBuf empty = new EmptyByteBuf(UnpooledByteBufAllocator.DEFAULT);
+        Assert.assertFalse(empty.isReadable());
+        Assert.assertFalse(empty.isReadable(1));
+    }
+}