Files
openide/java/java-tests/testData/inspection/dataFlow/fixture/GetClass.java
Tagir Valeev 9be22ca7e7 Do not assume that Object is assignable from any class
Class could be a primitive
Fixes IDEA-232014 False positive `Constant conditions & exceptions` inspection for `Class#isAssignableFrom(Class)`

GitOrigin-RevId: 4db7cfa10a0d2b8a2476f434db82d04d7a62cd38
2020-02-04 10:35:34 +00:00

94 lines
4.0 KiB
Java

import java.util.*;
class GetClass {
native void unknown();
public static void testIntClass() {
Class<?> cls = someIntClass();
System.out.println(Object.class.isAssignableFrom(cls));
}
public static Class<?> someIntClass() {
return int.class;
}
void testStability(Object obj, Class<?> c) {
if (obj.getClass().equals(c)) {
unknown();
if (<warning descr="Condition 'obj.getClass().equals(c)' is always 'true'">obj.getClass().equals(c)</warning>) { }
}
if (obj.getClass().equals(ArrayList.class)) {
unknown();
if (<warning descr="Condition 'obj.getClass().equals(ArrayList.class)' is always 'true'">obj.getClass().equals(ArrayList.class)</warning>) { }
}
}
void testFinalClass(String s) {
if (<warning descr="Condition 's.getClass() == String.class' is always 'true'">s.getClass() == String.class</warning>) { }
if (<warning descr="Condition 'String.class.equals(s.getClass())' is always 'true'">String.class.equals(s.getClass())</warning>) {}
}
void testNew() {
Object x = new HashSet();
if (<warning descr="Condition 'x.getClass() == HashSet.class' is always 'true'">x.getClass() == HashSet.class</warning>) {}
}
void testInstanceOfInterop(Object obj) {
if (obj instanceof CharSequence) {
if (<warning descr="Condition 'obj.getClass() == Integer.class' is always 'false'">obj.getClass() == Integer.class</warning>) {}
}
if (obj.getClass() == HashSet.class) {
if (<warning descr="Condition 'obj instanceof Set' is always 'true'">obj instanceof Set</warning>) {}
if (<warning descr="Condition 'obj instanceof LinkedHashSet' is always 'false'">obj instanceof LinkedHashSet</warning>) {}
}
if (obj instanceof HashSet) {
if (obj.getClass() == HashSet.class) {} // possible but not always
if (obj.getClass() == LinkedHashSet.class) {} // also possible
}
}
void testInterfaceAbstract(Object obj, Class<?> c) {
if (<warning descr="Condition 'obj.getClass() == CharSequence.class' is always 'false'">obj.getClass() == CharSequence.class</warning>) {}
if (<warning descr="Condition 'obj.getClass().equals(Number.class)' is always 'false'">obj.getClass().equals(Number.class)</warning>) {}
if (c == Number.class || c == CharSequence.class) {
if (<warning descr="Condition 'obj.getClass() == c' is always 'false'">obj.getClass() == c</warning>) {}
}
}
void testPrimitive(Object obj) {
Class<?> c = int.class;
if (<warning descr="Condition 'obj.getClass() == c' is always 'false'">obj.getClass() == c</warning>) {}
if (<warning descr="Condition 'obj.getClass() == void.class' is always 'false'">obj.getClass() == void.class</warning>) {}
if (obj.getClass() == int[].class) {}
}
void testVoidType(Object obj) {
if (<warning descr="Condition 'obj.getClass() == Void.class' is always 'false'">obj.getClass() == Void.class</warning>) {}
}
void testIntermediateVar(Object obj) {
Class<?> c = obj.getClass();
if (<warning descr="Condition 'c == Number.class' is always 'false'">c == Number.class</warning>) {}
if (c == HashSet.class) {
if (<warning descr="Condition 'obj instanceof CharSequence' is always 'false'">obj instanceof CharSequence</warning>) {}
}
if (obj instanceof CharSequence) {
if (<warning descr="Condition 'c == HashSet.class' is always 'false'">c == HashSet.class</warning>) {}
}
}
void testTwoObjects(Object o1, Object o2) {
if (o1 instanceof CharSequence && o2 instanceof Integer) {
if (<warning descr="Condition 'o1.getClass() == o2.getClass()' is always 'false'">o1.getClass() == o2.getClass()</warning>) {}
}
if (o1.getClass() == o2.getClass()) {
if (o1 instanceof String) {
if(<warning descr="Condition 'o2.getClass() == Integer.class' is always 'false'">o2.getClass() == Integer.class</warning>) {}
}
if (o1 instanceof CharSequence) {
if (<warning descr="Condition 'o2 instanceof Integer' is always 'false'">o2 instanceof Integer</warning>) {}
}
}
}
}