| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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 org.apache.avro.reflect; |
| |
| import org.apache.avro.AvroRuntimeException; |
| |
| /** |
| * A few utility methods for using @link{java.misc.Unsafe}, mostly for private |
| * use. |
| * |
| * Use of Unsafe on Android is forbidden, as Android provides only a very |
| * limited functionality for this class compared to the JDK version. |
| * |
| */ |
| |
| class ReflectionUtil { |
| |
| private ReflectionUtil() { |
| } |
| |
| private static FieldAccess fieldAccess; |
| static { |
| resetFieldAccess(); |
| } |
| static void resetFieldAccess() { |
| // load only one implementation of FieldAccess |
| // so it is monomorphic and the JIT can inline |
| FieldAccess access = null; |
| try { |
| if (null == System.getProperty("avro.disable.unsafe")) { |
| FieldAccess unsafeAccess = load( |
| "org.apache.avro.reflect.FieldAccessUnsafe", FieldAccess.class); |
| if (validate(unsafeAccess)) { |
| access = unsafeAccess; |
| } |
| } |
| } catch (Throwable ignored) { |
| } |
| if (access == null) { |
| try { |
| FieldAccess reflectAccess = load( |
| "org.apache.avro.reflect.FieldAccessReflect", FieldAccess.class); |
| if (validate(reflectAccess)) { |
| access = reflectAccess; |
| } |
| } catch (Throwable oops) { |
| throw new AvroRuntimeException( |
| "Unable to load a functional FieldAccess class!"); |
| } |
| } |
| fieldAccess = access; |
| } |
| |
| private static <T> T load(String name, Class<T> type) throws Exception { |
| return ReflectionUtil.class.getClassLoader().loadClass(name) |
| .asSubclass(type).newInstance(); |
| } |
| |
| public static FieldAccess getFieldAccess() { |
| return fieldAccess; |
| } |
| |
| private static boolean validate(FieldAccess access) throws Exception { |
| return new AccessorTestClass().validate(access); |
| } |
| |
| private static final class AccessorTestClass { |
| private boolean b = true; |
| protected byte by = 0xf; |
| public char c = 'c'; |
| short s = 123; |
| int i = 999; |
| long l = 12345L; |
| float f = 2.2f; |
| double d = 4.4d; |
| Object o = "foo"; |
| Integer i2 = 555; |
| |
| private boolean validate(FieldAccess access) throws Exception { |
| boolean valid = true; |
| valid &= validField(access, "b", b, false); |
| valid &= validField(access, "by", by, (byte) 0xaf); |
| valid &= validField(access, "c", c, 'C'); |
| valid &= validField(access, "s", s, (short) 321); |
| valid &= validField(access, "i", i, 111); |
| valid &= validField(access, "l", l, 54321L); |
| valid &= validField(access, "f", f, 0.2f); |
| valid &= validField(access, "d", d, 0.4d); |
| valid &= validField(access, "o", o, new Object()); |
| valid &= validField(access, "i2", i2, -555); |
| return valid; |
| } |
| |
| private boolean validField(FieldAccess access, String name, |
| Object original, Object toSet) throws Exception { |
| FieldAccessor a; |
| boolean valid = true; |
| a = accessor(access, name); |
| valid &= original.equals(a.get(this)); |
| a.set(this, toSet); |
| valid &= !original.equals(a.get(this)); |
| return valid; |
| } |
| |
| private FieldAccessor accessor(FieldAccess access, String name) |
| throws Exception { |
| return access.getAccessor(this.getClass().getDeclaredField(name)); |
| } |
| } |
| |
| } |