content: /*
   * Copyright (C) 2010 The Android Open Source Project
   *
   * Licensed 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 android.animation;
  
  import com.android.layoutlib.bridge.Bridge;
  import com.android.layoutlib.bridge.impl.DelegateManager;
  import com.android.tools.layoutlib.annotations.LayoutlibDelegate;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.Arrays;
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * Delegate implementing the native methods of android.animation.PropertyValuesHolder
   *
   * Through the layoutlib_create tool, the original native methods of PropertyValuesHolder have been
   * replaced by calls to methods of the same name in this delegate class.
   *
   * Because it's a stateless class to start with, there's no need to keep a {@link DelegateManager}
   * around to map int to instance of the delegate.
   *
   * The main goal of this class' methods are to provide a native way to access setters and getters
   * on some object. We override these methods to use reflection since the original reflection
   * implementation of the PropertyValuesHolder won't be able to access protected methods.
   *
   */
  /*package*/
  @SuppressWarnings("unused")
  class PropertyValuesHolder_Delegate {
      // This code is copied from android.animation.PropertyValuesHolder and must be kept in sync
      // We try several different types when searching for appropriate setter/getter functions.
      // The caller may have supplied values in a type that does not match the setter/getter
      // functions (such as the integers 0 and 1 to represent floating point values for alpha).
      // Also, the use of generics in constructors means that we end up with the Object versions
      // of primitive types (Float vs. float). But most likely, the setter/getter functions
      // will take primitive types instead.
      // So we supply an ordered array of other types to try before giving up.
      private static Class[] FLOAT_VARIANTS = {float.class, Float.class, double.class, int.class,
              Double.class, Integer.class};
      private static Class[] INTEGER_VARIANTS = {int.class, Integer.class, float.class, double.class,
              Float.class, Double.class};
  
      private static final Object sMethodIndexLock = new Object();
      private static final Map<Long, Method> ID_TO_METHOD = new HashMap<Long, Method>();
      private static final Map<String, Long> METHOD_NAME_TO_ID = new HashMap<String, Long>();
      private static long sNextId = 1;
  
      private static long registerMethod(Class<?> targetClass, String methodName, Class[] types,
              int nArgs) {
          // Encode the number of arguments in the method name
          String methodIndexName = String.format("%1$s.%2$s#%3$d", targetClass.getSimpleName(),
                  methodName, nArgs);
          synchronized (sMethodIndexLock) {
              Long methodId = METHOD_NAME_TO_ID.get(methodIndexName);
  
              if (methodId != null) {
                  // The method was already registered
                  return methodId;
              }
  
              Class[] args = new Class[nArgs];
              Method method = null;
              for (Class typeVariant : types) {
                  for (int i = 0; i < nArgs; i++) {
                      args[i] = typeVariant;
                  }
                  try {
                      method = targetClass.getDeclaredMethod(methodName, args);
                  } catch (NoSuchMethodException ignore) {
                  }
              }
  
              if (method != null) {
                  methodId = sNextId++;
                  ID_TO_METHOD.put(methodId, method);
                  METHOD_NAME_TO_ID.put(methodIndexName, methodId);
  
                  return methodId;
              }
          }
  
          // Method not found
          return 0;
      }
  
      private static void callMethod(Object target, long methodID, Object... args) {
          Method method = ID_TO_METHOD.get(methodID);
          assert method != null;
  
          try {
              method.setAccessible(true);
              method.invoke(target, args);
          } catch (IllegalAccessException | InvocationTargetException e) {
              Bridge.getLog().error(null, "Unable to update property during animation", e, null);
          }
      }
  
      @LayoutlibDelegate
      /*package*/ static long nGetIntMethod(Class<?> targetClass, String methodName) {
          return nGetMultipleIntMethod(targetClass, methodName, 1);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nGetFloatMethod(Class<?> targetClass, String methodName) {
          return nGetMultipleFloatMethod(targetClass, methodName, 1);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nGetMultipleIntMethod(Class<?> targetClass, String methodName,
              int numParams) {
          return registerMethod(targetClass, methodName, INTEGER_VARIANTS, numParams);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nGetMultipleFloatMethod(Class<?> targetClass, String methodName,
              int numParams) {
          return registerMethod(targetClass, methodName, FLOAT_VARIANTS, numParams);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallIntMethod(Object target, long methodID, int arg) {
          callMethod(target, methodID, arg);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallFloatMethod(Object target, long methodID, float arg) {
          callMethod(target, methodID, arg);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallTwoIntMethod(Object target, long methodID, int arg1,
              int arg2) {
          callMethod(target, methodID, arg1, arg2);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallFourIntMethod(Object target, long methodID, int arg1,
              int arg2, int arg3, int arg4) {
          callMethod(target, methodID, arg1, arg2, arg3, arg4);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallMultipleIntMethod(Object target, long methodID,
              int[] args) {
          assert args != null;
  
          // Box parameters
          Object[] params = new Object[args.length];
          for (int i = 0; i < args.length; i++) {
              params[i] = args;
          }
          callMethod(target, methodID, params);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallTwoFloatMethod(Object target, long methodID, float arg1,
              float arg2) {
          callMethod(target, methodID, arg1, arg2);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallFourFloatMethod(Object target, long methodID, float arg1,
              float arg2, float arg3, float arg4) {
          callMethod(target, methodID, arg1, arg2, arg3, arg4);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCallMultipleFloatMethod(Object target, long methodID,
              float[] args) {
          assert args != null;
  
          // Box parameters
          Object[] params = new Object[args.length];
          for (int i = 0; i < args.length; i++) {
              params[i] = args;
          }
          callMethod(target, methodID, params);
      }
  }
  