michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.tests.helpers;
michael@0: 
michael@0: import static org.mozilla.gecko.tests.helpers.AssertionHelper.fFail;
michael@0: 
michael@0: import java.lang.reflect.Field;
michael@0: 
michael@0: import android.content.Context;
michael@0: import android.view.View;
michael@0: 
michael@0: /**
michael@0:  * Provides helper functions for accessing Android framework features
michael@0:  *
michael@0:  * This class uses reflection to access framework functionalities that are
michael@0:  * unavailable through the regular Android API. Using reflection in this
michael@0:  * case is okay because it does not touch Gecko classes that go through
michael@0:  * ProGuard.
michael@0:  */
michael@0: public final class FrameworkHelper {
michael@0: 
michael@0:     private FrameworkHelper() { /* To disallow instantiation. */ }
michael@0: 
michael@0:     private static Field getClassField(final Class<?> clazz, final String fieldName)
michael@0:             throws NoSuchFieldException {
michael@0:         Class<?> cls = clazz;
michael@0:         do {
michael@0:             try {
michael@0:                 return cls.getDeclaredField(fieldName);
michael@0:             } catch (final NoSuchFieldException e) {
michael@0:                 cls = cls.getSuperclass();
michael@0:             }
michael@0:         } while (cls != null);
michael@0:         // We tried getDeclaredField before; now try getField instead.
michael@0:         // getField behaves differently in that getField traverses the inheritance
michael@0:         // list, but it only works on public fields. While getField won't get us
michael@0:         // anything new, it makes code cleaner by throwing an exception for us.
michael@0:         return clazz.getField(fieldName);
michael@0:     }
michael@0: 
michael@0:     private static Object getField(final Object obj, final String fieldName) {
michael@0:         try {
michael@0:             final Field field = getClassField(obj.getClass(), fieldName);
michael@0:             final boolean accessible = field.isAccessible();
michael@0:             field.setAccessible(true);
michael@0:             final Object ret = field.get(obj);
michael@0:             field.setAccessible(accessible);
michael@0:             return ret;
michael@0:         } catch (final NoSuchFieldException e) {
michael@0:             // We expect a valid field name; if it's not valid,
michael@0:             // the caller is doing something wrong and should be fixed.
michael@0:             fFail("Argument field should be a valid field name: " + e.toString());
michael@0:         } catch (final IllegalAccessException e) {
michael@0:             // This should not happen. If it does, setAccessible above is not working.
michael@0:             fFail("Field should be accessible: " + e.toString());
michael@0:         }
michael@0:         throw new IllegalStateException("Should not continue from previous failures");
michael@0:     }
michael@0: 
michael@0:     private static void setField(final Object obj, final String fieldName, final Object value) {
michael@0:         try {
michael@0:             final Field field = getClassField(obj.getClass(), fieldName);
michael@0:             final boolean accessible = field.isAccessible();
michael@0:             field.setAccessible(true);
michael@0:             field.set(obj, value);
michael@0:             field.setAccessible(accessible);
michael@0:             return;
michael@0:         } catch (final NoSuchFieldException e) {
michael@0:             // We expect a valid field name; if it's not valid,
michael@0:             // the caller is doing something wrong and should be fixed.
michael@0:             fFail("Argument field should be a valid field name: " + e.toString());
michael@0:         } catch (final IllegalAccessException e) {
michael@0:             // This should not happen. If it does, setAccessible above is not working.
michael@0:             fFail("Field should be accessible: " + e.toString());
michael@0:         }
michael@0:         throw new IllegalStateException("Cannot continue from previous failures");
michael@0:     }
michael@0: 
michael@0:     public static Context getViewContext(final View v) {
michael@0:         return (Context) getField(v, "mContext");
michael@0:     }
michael@0: 
michael@0:     public static void setViewContext(final View v, final Context c) {
michael@0:         setField(v, "mContext", c);
michael@0:     }
michael@0: }