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/*
* Copyright (C) 2015 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.
*/
public class Main {
static Object exactCheck = new ExactCheck();
static Object abstractCheckImpl = new AbstractCheckImpl();
static Object interfaceCheckImpl = new InterfaceCheckImpl();
static Object normalCheck = new NormalCheck();
static Object regularObject = new Object();
static Object objectArray = new Object[2];
static Object intArray = new int[2];
static Object doubleArray = new double[2];
static Object exactArray = new ExactCheck[2];
static Object normalArray = new NormalCheck[2];
static Object field;
public static void main(String[] args) {
checkInstanceOfNonTryCatch();
// We also check for a method with try/catch because the compiler then makes a slow
// path unconditionally save its live registers.
checkInstanceOfTryCatch();
checkCheckCast();
}
public static void checkInstanceOfNonTryCatch() {
check(true, exactCheck instanceof ExactCheck);
check(false, regularObject instanceof ExactCheck);
check(true, abstractCheckImpl instanceof AbstractCheck);
check(false, regularObject instanceof AbstractCheck);
check(true, interfaceCheckImpl instanceof InterfaceCheck);
check(false, regularObject instanceof InterfaceCheck);
check(true, normalCheck instanceof NormalCheck);
check(true, exactCheck instanceof NormalCheck);
check(false, regularObject instanceof NormalCheck);
check(false, regularObject instanceof int[]);
check(false, objectArray instanceof int[]);
check(true, intArray instanceof int[]);
check(false, doubleArray instanceof int[]);
check(false, regularObject instanceof ExactCheck[]);
check(false, objectArray instanceof ExactCheck[]);
check(false, doubleArray instanceof ExactCheck[]);
check(true, exactArray instanceof ExactCheck[]);
check(false, normalArray instanceof ExactCheck[]);
check(false, regularObject instanceof NormalCheck[]);
check(false, objectArray instanceof NormalCheck[]);
check(false, doubleArray instanceof NormalCheck[]);
check(true, exactArray instanceof NormalCheck[]);
check(true, normalArray instanceof NormalCheck[]);
check(false, regularObject instanceof Object[]);
check(true, objectArray instanceof Object[]);
check(false, doubleArray instanceof Object[]);
check(true, exactArray instanceof Object[]);
check(true, normalArray instanceof Object[]);
}
public static void checkInstanceOfTryCatch() {
try {
check(true, exactCheck instanceof ExactCheck);
check(false, regularObject instanceof ExactCheck);
check(true, abstractCheckImpl instanceof AbstractCheck);
check(false, regularObject instanceof AbstractCheck);
check(true, interfaceCheckImpl instanceof InterfaceCheck);
check(false, regularObject instanceof InterfaceCheck);
check(true, normalCheck instanceof NormalCheck);
check(true, exactCheck instanceof NormalCheck);
check(false, regularObject instanceof NormalCheck);
check(false, regularObject instanceof int[]);
check(false, objectArray instanceof int[]);
check(true, intArray instanceof int[]);
check(false, doubleArray instanceof int[]);
check(false, regularObject instanceof ExactCheck[]);
check(false, objectArray instanceof ExactCheck[]);
check(false, doubleArray instanceof ExactCheck[]);
check(true, exactArray instanceof ExactCheck[]);
check(false, normalArray instanceof ExactCheck[]);
check(false, regularObject instanceof NormalCheck[]);
check(false, objectArray instanceof NormalCheck[]);
check(false, doubleArray instanceof NormalCheck[]);
check(true, exactArray instanceof NormalCheck[]);
check(true, normalArray instanceof NormalCheck[]);
check(false, regularObject instanceof Object[]);
check(true, objectArray instanceof Object[]);
check(false, doubleArray instanceof Object[]);
check(true, exactArray instanceof Object[]);
check(true, normalArray instanceof Object[]);
} catch (Throwable t) {
throw new Error("Unreachable");
}
}
public static void check(boolean expected, boolean actual) {
if (actual != expected) {
throw new Error("Expected " + expected + ", got " + actual);
}
}
public static void checkCheckCast() {
// Exact check.
field = (ExactCheck)exactCheck;
try {
field = (ExactCheck)regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Abstract check.
field = (AbstractCheck)abstractCheckImpl;
try {
field = (AbstractCheck)regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Interface check.
field = (InterfaceCheck)interfaceCheckImpl;
try {
field = (InterfaceCheck)regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Normal check.
field = (NormalCheck)normalCheck;
field = (NormalCheck)exactCheck;
try {
field = (NormalCheck)regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Primitive array check.
try {
field = (int[])regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
try {
field = (int[])objectArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
field = (int[])intArray;
try {
field = (int[])doubleArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Array with final component type check.
try {
field = (ExactCheck[])regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
try {
field = (ExactCheck[])objectArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
try {
field = (ExactCheck[])doubleArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
field = (ExactCheck[])exactArray;
try {
field = (ExactCheck[])normalArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
// Array with non final component type check.
try {
field = (NormalCheck[])regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
try {
field = (NormalCheck[])objectArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
try {
field = (NormalCheck[])doubleArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
field = (NormalCheck[])exactArray;
field = (NormalCheck[])normalArray;
// Object[] check.
try{
field = (Object[])regularObject;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
field = (Object[])objectArray;
try {
field = (Object[])doubleArray;
throw new Error("Can't reach here");
} catch (ClassCastException ignore) {}
field = (Object[])exactArray;
field = (Object[])normalArray;
}
}
class NormalCheck {
}
final class ExactCheck extends NormalCheck {
}
abstract class AbstractCheck {
}
class AbstractCheckImpl extends AbstractCheck {
}
interface InterfaceCheck {
}
class InterfaceCheckImpl implements InterfaceCheck {
}
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