Attachment #147852 for bug #287676




		"",
		JavacTestOptions.SKIP);
}
// https://bugs.eclipse.org/bugs/show_bug.cgi?id=287676
// Test to make sure that an unnecessary cast warning is produced in case of
// wrapper types like Integer, Character, Short, Byte, etc.
public void test047() {
	CompilerOptions options = new CompilerOptions(getCompilerOptions());
	if(options.sourceLevel >= ClassFileConstants.JDK1_5){
		String expectedOutput = 
				"----------\n" +
				"1. WARNING in X.java (at line 5)\n" +
				"	a = (Integer)a + (Integer)2;\n" +
				"	    ^^^^^^^^^^\n" +
				"Unnecessary cast from Integer to Integer\n" +
				"----------\n" +
				"2. WARNING in X.java (at line 5)\n" +
				"	a = (Integer)a + (Integer)2;\n" +
				"	                 ^^^^^^^^^^\n" +
				"Unnecessary cast from int to Integer\n" +
				"----------\n" +
				"3. WARNING in X.java (at line 6)\n" +
				"	if ((Character)aList.get(0) == 'c')\n" +
				"	    ^^^^^^^^^^^^^^^^^^^^^^^\n" +
				"Unnecessary cast from Character to Character\n" +
				"----------\n";


		this.runNegativeTest(
				new String[] {
						"X.java",
						"import java.util.ArrayList;\n" +
						"public class X{\n" +
						"	void test() {" +
						"		Integer a = 1;\n" +
						"		ArrayList<Character> aList = new ArrayList<Character>(1);\n" +
						"		a = (Integer)a + (Integer)2;\n" +
						"		if ((Character)aList.get(0) == 'c')\n" +
						"			System.out.println();\n" +
						"	}\n" +
						"}\n"
				},
				expectedOutput);
	}
}
public static Class testClass() {
	return CastTest.class;
}





	// check need for left operand cast
	int alternateLeftTypeId = leftTypeId;
	boolean unnecessaryLeftCast = (left.bits & ASTNode.UnnecessaryCast) != 0;
	boolean unnecessaryRightCast = (right.bits & ASTNode.UnnecessaryCast) != 0;
	if (leftIsCast) {
		if (!unnecessaryLeftCast && left.resolvedType.isBaseType()) {
			// narrowing conversion on base type may change value, thus necessary
			leftIsCast = false;
		} else  {
			TypeBinding alternateLeftType = ((CastExpression)left).expression.resolvedType;
			if (alternateLeftType == null) return; // cannot do better
			if ((alternateLeftTypeId = alternateLeftType.id) == leftTypeId || scope.environment().computeBoxingType(alternateLeftType).id == leftTypeId) { // obvious identity cast
				scope.problemReporter().unnecessaryCast((CastExpression)left);
				leftIsCast = false;
			} else if (alternateLeftTypeId == TypeIds.T_null) {

	// check need for right operand cast
	int alternateRightTypeId = rightTypeId;
	if (rightIsCast) {
		if (!unnecessaryRightCast && right.resolvedType.isBaseType()) {
			// narrowing conversion on base type may change value, thus necessary
			rightIsCast = false;
		} else {
			TypeBinding alternateRightType = ((CastExpression)right).expression.resolvedType;
			if (alternateRightType == null) return; // cannot do better
			if ((alternateRightTypeId = alternateRightType.id) == rightTypeId || scope.environment().computeBoxingType(alternateRightType).id == rightTypeId) { // obvious identity cast
				scope.problemReporter().unnecessaryCast((CastExpression)right);
				rightIsCast = false;
			} else if (alternateRightTypeId == TypeIds.T_null) {

Return to bug 287676

Lines 1744-1749 Link Here

(-)src/org/eclipse/jdt/core/tests/compiler/regression/CastTest.java (+42 lines)
1744	"",	1744	"",
1745	JavacTestOptions.SKIP);	1745	JavacTestOptions.SKIP);
1746	}	1746	}
		1747	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=287676
		1748	// Test to make sure that an unnecessary cast warning is produced in case of
		1749	// wrapper types like Integer, Character, Short, Byte, etc.
		1750	public void test047() {
		1751	CompilerOptions options = new CompilerOptions(getCompilerOptions());
		1752	if(options.sourceLevel >= ClassFileConstants.JDK1_5){
		1753	String expectedOutput =
		1754	"----------\n" +
		1755	"1. WARNING in X.java (at line 5)\n" +
		1756	" a = (Integer)a + (Integer)2;\n" +
		1757	" ^^^^^^^^^^\n" +
		1758	"Unnecessary cast from Integer to Integer\n" +
		1759	"----------\n" +
		1760	"2. WARNING in X.java (at line 5)\n" +
		1761	" a = (Integer)a + (Integer)2;\n" +
		1762	" ^^^^^^^^^^\n" +
		1763	"Unnecessary cast from int to Integer\n" +
		1764	"----------\n" +
		1765	"3. WARNING in X.java (at line 6)\n" +
		1766	" if ((Character)aList.get(0) == 'c')\n" +
		1767	" ^^^^^^^^^^^^^^^^^^^^^^^\n" +
		1768	"Unnecessary cast from Character to Character\n" +
		1769	"----------\n";
		1770
		1771
		1772	this.runNegativeTest(
		1773	new String[] {
		1774	"X.java",
		1775	"import java.util.ArrayList;\n" +
		1776	"public class X{\n" +
		1777	" void test() {" +
		1778	" Integer a = 1;\n" +
		1779	" ArrayList<Character> aList = new ArrayList<Character>(1);\n" +
		1780	" a = (Integer)a + (Integer)2;\n" +
		1781	" if ((Character)aList.get(0) == 'c')\n" +
		1782	" System.out.println();\n" +
		1783	" }\n" +
		1784	"}\n"
		1785	},
		1786	expectedOutput);
		1787	}
		1788	}
1747	public static Class testClass() {	1789	public static Class testClass() {
1748	return CastTest.class;	1790	return CastTest.class;
1749	}	1791	}

Lines 192-205 Link Here

(-)compiler/org/eclipse/jdt/internal/compiler/ast/CastExpression.java (-4 / +6 lines)
192		192
193	// check need for left operand cast	193	// check need for left operand cast
194	int alternateLeftTypeId = leftTypeId;	194	int alternateLeftTypeId = leftTypeId;
		195	boolean unnecessaryLeftCast = (left.bits & ASTNode.UnnecessaryCast) != 0;
		196	boolean unnecessaryRightCast = (right.bits & ASTNode.UnnecessaryCast) != 0;
195	if (leftIsCast) {	197	if (leftIsCast) {
196	if ((left.bits & ASTNode.UnnecessaryCast) == 0 && left.resolvedType.isBaseType()) {	198	if (!unnecessaryLeftCast && left.resolvedType.isBaseType()) {
197	// narrowing conversion on base type may change value, thus necessary	199	// narrowing conversion on base type may change value, thus necessary
198	leftIsCast = false;	200	leftIsCast = false;
199	} else {	201	} else {
200	TypeBinding alternateLeftType = ((CastExpression)left).expression.resolvedType;	202	TypeBinding alternateLeftType = ((CastExpression)left).expression.resolvedType;
201	if (alternateLeftType == null) return; // cannot do better	203	if (alternateLeftType == null) return; // cannot do better
202	if ((alternateLeftTypeId = alternateLeftType.id) == leftTypeId) { // obvious identity cast	204	if ((alternateLeftTypeId = alternateLeftType.id) == leftTypeId \|\| scope.environment().computeBoxingType(alternateLeftType).id == leftTypeId) { // obvious identity cast
203	scope.problemReporter().unnecessaryCast((CastExpression)left);	205	scope.problemReporter().unnecessaryCast((CastExpression)left);
204	leftIsCast = false;	206	leftIsCast = false;
205	} else if (alternateLeftTypeId == TypeIds.T_null) {	207	} else if (alternateLeftTypeId == TypeIds.T_null) {
Lines 211-223 Link Here
211	// check need for right operand cast	213	// check need for right operand cast
212	int alternateRightTypeId = rightTypeId;	214	int alternateRightTypeId = rightTypeId;
213	if (rightIsCast) {	215	if (rightIsCast) {
214	if ((right.bits & ASTNode.UnnecessaryCast) == 0 && right.resolvedType.isBaseType()) {	216	if (!unnecessaryRightCast && right.resolvedType.isBaseType()) {
215	// narrowing conversion on base type may change value, thus necessary	217	// narrowing conversion on base type may change value, thus necessary
216	rightIsCast = false;	218	rightIsCast = false;
217	} else {	219	} else {
218	TypeBinding alternateRightType = ((CastExpression)right).expression.resolvedType;	220	TypeBinding alternateRightType = ((CastExpression)right).expression.resolvedType;
219	if (alternateRightType == null) return; // cannot do better	221	if (alternateRightType == null) return; // cannot do better
220	if ((alternateRightTypeId = alternateRightType.id) == rightTypeId) { // obvious identity cast	222	if ((alternateRightTypeId = alternateRightType.id) == rightTypeId \|\| scope.environment().computeBoxingType(alternateRightType).id == rightTypeId) { // obvious identity cast
221	scope.problemReporter().unnecessaryCast((CastExpression)right);	223	scope.problemReporter().unnecessaryCast((CastExpression)right);
222	rightIsCast = false;	224	rightIsCast = false;
223	} else if (alternateRightTypeId == TypeIds.T_null) {	225	} else if (alternateRightTypeId == TypeIds.T_null) {