robolectric/src/main/java/org/robolectric/android/AndroidInterceptors.java

package org.robolectric.android;

import static java.lang.invoke.MethodHandles.constant;
import static java.lang.invoke.MethodHandles.dropArguments;
import static java.lang.invoke.MethodType.methodType;
import static java.util.Arrays.asList;

import android.content.Context;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.Locale;
import javax.annotation.Nullable;
import org.robolectric.internal.bytecode.Interceptor;
import org.robolectric.internal.bytecode.MethodRef;
import org.robolectric.internal.bytecode.MethodSignature;
import org.robolectric.shadows.ShadowSystemClock;
import org.robolectric.shadows.ShadowWindow;
import org.robolectric.util.Function;
import org.robolectric.util.ReflectionHelpers;

public class AndroidInterceptors {
  private static final MethodHandles.Lookup lookup = MethodHandles.lookup();

  public static Collection<Interceptor> all() {
    return asList(
        new LinkedHashMapEldestInterceptor(),
        new PolicyManagerMakeNewWindowInterceptor(),
        new SystemTimeInterceptor(),
        new SystemArrayCopyInterceptor(),
        new LocaleAdjustLanguageCodeInterceptor(),
        new SystemLogEInterceptor(),
        new NoOpInterceptor()
    );
  }

//  @Intercept(value = LinkedHashMap.class, method = "eldest")
  public static class LinkedHashMapEldestInterceptor extends Interceptor {
    public LinkedHashMapEldestInterceptor() {
      super(new MethodRef(LinkedHashMap.class, "eldest"));
    }

    @Nullable
    static Object eldest(LinkedHashMap map) {
      return map.isEmpty() ? null : map.entrySet().iterator().next();
    }

    @Override
    public Function<Object, Object> handle(MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          return eldest((LinkedHashMap) value);
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      return lookup.findStatic(getClass(), "eldest",
          methodType(Object.class, LinkedHashMap.class));
    }
  }

  public static class PolicyManagerMakeNewWindowInterceptor extends Interceptor {
    public PolicyManagerMakeNewWindowInterceptor() {
      super(new MethodRef("com.android.internal.policy.PolicyManager", "makeNewWindow"));
    }

    @Override
    public Function<Object, Object> handle(MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          ClassLoader cl = theClass.getClassLoader();

          try {
            Class<?> shadowWindowClass = cl.loadClass("org.robolectric.shadows.ShadowWindow");
            Class<?> activityClass = cl.loadClass(Context.class.getName());
            Object context = params[0];
            return ReflectionHelpers.callStaticMethod(shadowWindowClass, "create", ReflectionHelpers.ClassParameter.from(activityClass, context));
          } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
          }
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      Class<?> shadowWindowClass;
      try {
        shadowWindowClass = type.returnType().getClassLoader().loadClass(ShadowWindow.class.getName());
      } catch (ClassNotFoundException e) {
        throw new RuntimeException(e);
      }
      return lookup.in(type.returnType()).findStatic(shadowWindowClass, "create", type);
    }
  }

  public static class SystemTimeInterceptor extends Interceptor {
    public SystemTimeInterceptor() {
      super(new MethodRef(System.class, "nanoTime"), new MethodRef(System.class, "currentTimeMillis"));
    }

    @Override
    public Function<Object, Object> handle(final MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          ClassLoader cl = theClass.getClassLoader();
          try {
            Class<?> shadowSystemClockClass = cl.loadClass("org.robolectric.shadows.ShadowSystemClock");
            return ReflectionHelpers.callStaticMethod(shadowSystemClockClass, methodSignature.methodName);
          } catch (ClassNotFoundException e) {
            throw new RuntimeException(e);
          }
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      switch (methodName) {
        case "nanoTime":
          return lookup.findStatic(ShadowSystemClock.class,
              "nanoTime", methodType(long.class));
        case "currentTimeMillis":
          return lookup.findStatic(ShadowSystemClock.class,
              "currentTimeMillis", methodType(long.class));
      }
      throw new UnsupportedOperationException();
    }
  }

  public static class SystemArrayCopyInterceptor extends Interceptor {
    public SystemArrayCopyInterceptor() {
      super(new MethodRef(System.class, "arraycopy"));
    }

    @Override
    public Function<Object, Object> handle(MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          //noinspection SuspiciousSystemArraycopy
          System.arraycopy(params[0], (Integer) params[1], params[2], (Integer) params[3], (Integer) params[4]);
          return null;
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      return lookup.findStatic(System.class, "arraycopy",
          methodType(void.class, Object.class, int.class, Object.class, int.class, int.class));
    }
  }

  public static class LocaleAdjustLanguageCodeInterceptor extends Interceptor {
    public LocaleAdjustLanguageCodeInterceptor() {
      super(new MethodRef(Locale.class, "adjustLanguageCode"));
    }

    static String adjustLanguageCode(String languageCode) {
      String adjusted = languageCode.toLowerCase(Locale.US);
      // Map new language codes to the obsolete language
      // codes so the correct resource bundles will be used.
      if (languageCode.equals("he")) {
        adjusted = "iw";
      } else if (languageCode.equals("id")) {
        adjusted = "in";
      } else if (languageCode.equals("yi")) {
        adjusted = "ji";
      }

      return adjusted;
    }

    @Override
    public Function<Object, Object> handle(MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          return adjustLanguageCode((String) params[0]);
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      return lookup.findStatic(getClass(), "adjustLanguageCode",
          methodType(String.class, String.class));
    }
  }

  public static class SystemLogEInterceptor extends Interceptor {
    public SystemLogEInterceptor() {
      super(new MethodRef(System.class.getName(), "logE"));
    }

    static void logE(Object... params) {
      String message = "System.logE: ";
      for (Object param : params) {
        message += param.toString();
      }
      System.err.println(message);
    }

    @Override
    public Function<Object, Object> handle(MethodSignature methodSignature) {
      return new Function<Object, Object>() {
        @Override
        public Object call(Class<?> theClass, Object value, Object[] params) {
          logE(params);
          return null;
        }
      };
    }

    @Override
    public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      return lookup.findStatic(getClass(), "logE",
          methodType(void.class, Object[].class));
    }
  }

  public static class NoOpInterceptor extends Interceptor {
    public NoOpInterceptor() {
      super(
          new MethodRef("java.lang.System", "loadLibrary"),
          new MethodRef("android.os.StrictMode", "trackActivity"),
          new MethodRef("android.os.StrictMode", "incrementExpectedActivityCount"),
          new MethodRef("android.util.LocaleUtil", "getLayoutDirectionFromLocale"),
          new MethodRef("android.view.FallbackEventHandler", "*"),
          new MethodRef("android.view.IWindowSession", "*")
      );
    }

    @Override public Function<Object, Object> handle(MethodSignature methodSignature) {
      return returnDefaultValue(methodSignature);
    }

    @Override public MethodHandle getMethodHandle(String methodName, MethodType type) throws NoSuchMethodException, IllegalAccessException {
      MethodHandle nothing = constant(Void.class, null).asType(methodType(void.class));

      if (type.parameterCount() != 0) {
        return dropArguments(nothing, 0, type.parameterArray());
      } else {
        return nothing;
      }
    }
  }
}