content: /*******************************************************************************
   * Copyright 2013 Alexandros Schillings
   * 
   * 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 co.uk.alt236.reflectivedrawableloader;
  
  import java.lang.reflect.Field;
  import java.util.HashMap;
  import java.util.Map;
  
  import android.util.Log;
  
  class ReflectionUtils {
  	private final String TAG = getClass().getName();
  	protected final static String RESOURCE_LOCATION_DRAWABLES = ".R.drawable";
  
  	private final String mPackageName;
  	private final Map<String, Class<?>> mClassCache;
  
  	protected ReflectionUtils(String appPackageName) {
  		Log.d(TAG, "New ReflectionUtils() for '" + appPackageName + "'");
  		mPackageName = appPackageName;
  		mClassCache = new HashMap<String, Class<?>>();
  	}
  
  	private Class<?> getResourceClass(final String suffix) {
  		if(mClassCache.containsKey(suffix)){
  			return mClassCache.get(suffix);
  		} else {
  			try {
  				final Class<?> rClassBase = Class.forName(mPackageName + ".R");
  				final Class<?>[] subClassTable = rClassBase.getDeclaredClasses();
  
  				for (Class<?> subClass : subClassTable) {
  					if (subClass.getCanonicalName().endsWith(suffix)) {
  						mClassCache.put(suffix, subClass);
  						return subClass;
  					}
  				}
  
  			} catch (ClassNotFoundException e) {
  				Log.e(TAG, "getResourceClass() ClassNotFoundException: " + e.getMessage(), e);
  			}
  
  			Log.e(TAG, "getResourceClass() Unable to find Sublass: " + suffix);
  
  			return null;
  		}
  	}
  
  	public void logFields(String resourceLocation) {
  		Log.d(TAG, "logFields() Getting Fields for '" + resourceLocation + "' ============= ");
  
  		try {
  			final Field[] fields = getResourceClass(resourceLocation).getFields();
  			for (Field field : fields) {
  				Log.d(TAG, "logFields() Field: '" + field.getName() + "'");
  			}
  		} catch (NullPointerException e) {}
  	}
  
  	public void logSubClasses(String baseClass) {
  		Log.d(TAG, "logSubClasses() Getting subclasses for '" + baseClass + "' ============= ");
  
  		try {
  			final Class<?> rClass = Class.forName(baseClass);
  			final Class<?>[] subClassTable = rClass.getDeclaredClasses();
  			
  			for (final Class<?> subclass : subClassTable) {
  				Log.d(TAG, "logSubClasses() Class: " + subclass.getCanonicalName());
  			}
  
  		} catch (Exception e) {
  			Log.e(TAG, "logSubClasses() Error: " + e.getMessage(), e);
  		}
  	}
  
  	protected int reflectDrawable(String fieldName, int defaultValue, boolean reportFailure) {
  		return reflectResource(RESOURCE_LOCATION_DRAWABLES, fieldName, defaultValue, reportFailure);
  	}
  
  	private int reflectResource(String resourceLocation, String fieldName, int defaultValue, boolean reportFailure) {
  		int error = 0;
  		try {
  			final Field field = getResourceClass(resourceLocation).getField(fieldName);
  			return field.getInt(null);
  		} catch (NoSuchFieldException e) {
  			error = 1;
  		} catch (IllegalAccessException e) {
  			error = 2;
  		} catch (NullPointerException e) {
  			error = 3;
  		}
  
  		if (reportFailure) {
  			Log.w(TAG, "reflectResource() Resource '" + fieldName + "' not available! (" + error +")");
  		}
  
  		return defaultValue;
  	}
  }
  