/* * Copyright (C) 2012 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. */ import java.lang.reflect.Array; import java.lang.reflect.Field; import java.lang.reflect.Method; public class Main { public static void main(String[] args) throws Exception { arrayAccess(); arrayStore(); classCast(); classNotFound(); negativeArraySize(); nullPointers(); reflection(); stringIndex(); } private static void assertEquals(String expected, String actual) { if (expected == null && actual == null) { return; } if (expected != null && expected.equals(actual)) { return; } throw new AssertionError("not equal\n" + "expected: " + expected + "\n" + "actual: " + actual); } private static void fail() { throw new AssertionError(); } private static void arrayAccess() throws Exception { byte[] bs = new byte[1]; double[] ds = new double[1]; Object[] os = new Object[1]; // aput try { bs[2] = 0; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } // aget try { byte b = bs[2]; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } // aput-wide try { ds[2] = 0.0; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } // aget-wide try { double d = ds[2]; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } // aput-object try { os[2] = null; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } // aget-object try { Object o = os[2]; fail(); } catch (ArrayIndexOutOfBoundsException ex) { assertEquals("length=1; index=2", ex.getMessage()); } } private static void arrayStore() throws Exception { try { Object[] array = new String[10]; Object o = new Exception(); array[0] = o; fail(); } catch (ArrayStoreException ex) { assertEquals("java.lang.Exception cannot be stored in an array of type java.lang.String[]", ex.getMessage()); } try { Object[] array = new C[10][]; Object o = new Integer(5); array[0] = o; fail(); } catch (ArrayStoreException ex) { assertEquals("java.lang.Integer cannot be stored in an array of type Main$C[][]", ex.getMessage()); } try { Object[] array = new Float[10][]; Object o = new C[4]; array[0] = o; fail(); } catch (ArrayStoreException ex) { assertEquals("Main$C[] cannot be stored in an array of type java.lang.Float[][]", ex.getMessage()); } try { String[] src = new String[] { null, null, null, null, "hello", "goodbye" }; Integer[] dst = new Integer[10]; System.arraycopy(src, 1, dst, 0, 5); } catch (ArrayStoreException ex) { assertEquals("source[4] of type java.lang.String cannot be stored in destination array of type java.lang.Integer[]", ex.getMessage()); } try { String[] src = new String[1]; int[] dst = new int[1]; System.arraycopy(src, 0, dst, 0, 1); } catch (ArrayStoreException ex) { assertEquals("Incompatible types: src=java.lang.String[], dst=int[]", ex.getMessage()); } try { float[] src = new float[1]; Runnable[] dst = new Runnable[1]; System.arraycopy(src, 0, dst, 0, 1); } catch (ArrayStoreException ex) { assertEquals("Incompatible types: src=float[], dst=java.lang.Runnable[]", ex.getMessage()); } try { boolean[] src = new boolean[1]; double[][] dst = new double[1][]; System.arraycopy(src, 0, dst, 0, 1); } catch (ArrayStoreException ex) { assertEquals("Incompatible types: src=boolean[], dst=double[][]", ex.getMessage()); } try { String src = "hello"; Object[] dst = new Object[1]; System.arraycopy(src, 0, dst, 0, 1); } catch (ArrayStoreException ex) { assertEquals("source of type java.lang.String is not an array", ex.getMessage()); } try { Object[] src = new Object[1]; Integer dst = new Integer(5); System.arraycopy(src, 0, dst, 0, 1); } catch (ArrayStoreException ex) { assertEquals("destination of type java.lang.Integer is not an array", ex.getMessage()); } // This test demonstrates that the exception message complains // about the source in cases where neither source nor // destination is an array. try { System.arraycopy(new C(), 0, "hello", 0, 1); } catch (ArrayStoreException ex) { assertEquals("source of type Main$C is not an array", ex.getMessage()); } } private static void classCast() throws Exception { // Reference types. try { Object o = new Exception(); String s = (String) o; fail(); } catch (ClassCastException ex) { assertEquals("java.lang.Exception cannot be cast to java.lang.String", ex.getMessage()); } // Arrays of reference types. try { Object o = (C) makeArray(String.class); fail(); } catch (ClassCastException ex) { assertEquals("java.lang.String[] cannot be cast to Main$C", ex.getMessage()); } // Arrays of primitives. try { Object o = (C) makeArray(float.class); fail(); } catch (ClassCastException ex) { assertEquals("float[] cannot be cast to Main$C", ex.getMessage()); } // Multi-dimensional arrays of primitives. try { Object o = (C) makeArray(char[].class); fail(); } catch (ClassCastException ex) { assertEquals("char[][] cannot be cast to Main$C", ex.getMessage()); } // Multi-dimensional arrays of references. try { Object o = (Object[][][]) makeInteger(); fail(); } catch (ClassCastException ex) { assertEquals("java.lang.Integer cannot be cast to java.lang.Object[][][]", ex.getMessage()); } } static class C { } /** * Helper for testCastOperator and testCastOperatorWithArrays. It's important that the * return type is Object, since otherwise the compiler will just reject the code. */ private static Object makeInteger() { return new Integer(5); } /** * Helper for testCastOperatorWithArrays. It's important that * the return type is Object. */ private static Object makeArray(Class c) { return Array.newInstance(c, 1); } private static void classNotFound() throws Exception { try { // There is no such thing as an array of void. Class.forName("[V"); fail(); } catch (ClassNotFoundException ex) { assertEquals("Invalid name: [V", ex.getMessage()); } try { // This class name is valid, but doesn't exist. Class.forName("package.Class"); fail(); } catch (ClassNotFoundException ex) { assertEquals("package.Class", ex.getMessage()); } try { // This array class name is valid, but the type doesn't exist. Class.forName("[[Lpackage.Class;"); fail(); } catch (ClassNotFoundException ex) { assertEquals("[[Lpackage.Class;", ex.getMessage()); } } private static void negativeArraySize() throws Exception { try { int[] is = new int[-123]; fail(); } catch (NegativeArraySizeException ex) { assertEquals("-123", ex.getMessage()); } } // Defeat the fact that null's are untyped for precise detail message creation with quickening. private static Object returnNullObject() { return null; } private static A returnNullA() { return null; } private static void nullPointers() throws Exception { // Invoke method. try { Object o = returnNullObject(); o.hashCode(); fail(); } catch (NullPointerException ex) { assertEquals("Attempt to invoke virtual method 'int java.lang.Object.hashCode()' on a null object reference", ex.getMessage()); } // Read field. try { A a = returnNullA(); int i = a.i; fail(); } catch (NullPointerException ex) { assertEquals("Attempt to read from field 'int A.i' on a null object reference", ex.getMessage()); } // Write field. try { A a = returnNullA(); a.i = 1; fail(); } catch (NullPointerException ex) { assertEquals("Attempt to write to field 'int A.i' on a null object reference", ex.getMessage()); } // Read array. try { int[] is = null; int i = is[0]; fail(); } catch (NullPointerException ex) { assertEquals("Attempt to read from null array", ex.getMessage()); } // Write array. try { int[] is = null; is[0] = 1; fail(); } catch (NullPointerException ex) { assertEquals("Attempt to write to null array", ex.getMessage()); } // Array length. try { int[] is = null; int i = is.length; fail(); } catch (NullPointerException ex) { assertEquals("Attempt to get length of null array", ex.getMessage()); } } private static void reflection() throws Exception { // Can't assign Integer to a String field. try { Field field = A.class.getField("b"); field.set(new A(), 5); fail(); } catch (IllegalArgumentException expected) { assertEquals("field A.b has type java.lang.String, got java.lang.Integer", expected.getMessage()); } // Can't unbox null to a primitive. try { Field field = A.class.getField("i"); field.set(new A(), null); fail(); } catch (IllegalArgumentException expected) { assertEquals("field A.i has type int, got null", expected.getMessage()); } // Can't unbox String to a primitive. try { Field field = A.class.getField("i"); field.set(new A(), "hello, world!"); fail(); } catch (IllegalArgumentException expected) { assertEquals("field A.i has type int, got java.lang.String", expected.getMessage()); } // Can't pass an Integer as a String. try { Method m = A.class.getMethod("m", int.class, String.class); m.invoke(new A(), 2, 2); fail(); } catch (IllegalArgumentException expected) { assertEquals("method A.m argument 2 has type java.lang.String, got java.lang.Integer", expected.getMessage()); } // Can't pass null as an int. try { Method m = A.class.getMethod("m", int.class, String.class); m.invoke(new A(), null, ""); fail(); } catch (IllegalArgumentException expected) { assertEquals("method A.m argument 1 has type int, got null", expected.getMessage()); } try { Method m = String.class.getMethod("charAt", int.class); m.invoke("hello"); // Wrong number of arguments. fail(); } catch (IllegalArgumentException iae) { assertEquals("Wrong number of arguments; expected 1, got 0", iae.getMessage()); } try { Method m = String.class.getMethod("charAt", int.class); m.invoke("hello", "world"); // Wrong type. fail(); } catch (IllegalArgumentException iae) { assertEquals("method java.lang.String.charAt argument 1 has type int, got java.lang.String", iae.getMessage()); } try { Method m = String.class.getMethod("charAt", int.class); m.invoke("hello", (Object) null); // Null for a primitive argument. fail(); } catch (IllegalArgumentException iae) { assertEquals("method java.lang.String.charAt argument 1 has type int, got null", iae.getMessage()); } try { Method m = String.class.getMethod("charAt", int.class); m.invoke(new Integer(5)); // Wrong type for 'this'. fail(); } catch (IllegalArgumentException iae) { assertEquals("Expected receiver of type java.lang.String, but got java.lang.Integer", iae.getMessage()); } try { Method m = String.class.getMethod("charAt", int.class); m.invoke(null); // Null for 'this'. fail(); } catch (NullPointerException npe) { assertEquals("null receiver", npe.getMessage()); } } private static void stringIndex() throws Exception { // charAt too small. try { "hello".charAt(-1); fail(); } catch (StringIndexOutOfBoundsException ex) { assertEquals("length=5; index=-1", ex.getMessage()); } // charAt too big. try { "hello".charAt(7); fail(); } catch (StringIndexOutOfBoundsException ex) { assertEquals("length=5; index=7", ex.getMessage()); } // substring too big. try { "hello there".substring(9,14); fail(); } catch (StringIndexOutOfBoundsException ex) { assertEquals("length=11; regionStart=9; regionLength=5", ex.getMessage()); } } } class A { public String b; public int i; public void m(int i, String s) {} }