Using a switch on a class field which is an interface implemented by an Enum without explicitly casting to an enum will use the default branch every time after obfuscating #483
Description
Replicated in Proguard 7.7.0 and JDK Temurin-21.0.7+6.
Simple reproduction case :
package org.example;
public class TestClass {
public interface TestInterface {
int getValue();
}
public enum TestEnum implements TestInterface {
A, B, C, D;
@Override
public int getValue() {
return ordinal();
}
}
private TestInterface m_field;
public void setField(final TestInterface field) {
m_field = field;
}
public int method1() {
switch (m_field) {
case TestEnum.A:
return 1;
case TestEnum.B:
return 2;
case TestEnum.C:
return 3;
case TestEnum.D:
return 4;
default:
return 100;
}
}
public int method2() {
switch ((TestEnum) m_field) {
case TestEnum.A:
return 1;
case TestEnum.B:
return 2;
case TestEnum.C:
return 3;
case TestEnum.D:
return 4;
default:
return 100;
}
}
public static void main(String[] args) {
final TestClass test = new TestClass();
test.setField(TestEnum.B);
System.out.println("test.method1()=" + test.method1());
System.out.println("test.method2()=" + test.method2());
}
}The complete project with the Maven's pom.xml is available in the given zip archive ProguardSwitchBug.zip. When running the command to obfuscate and run :
mvn clean package && java -cp target/ProguardSwitchBug-1.0-SNAPSHOT-shaded-obfuscated.jar org.example.TestClass
The output is
test.method1()=100
test.method2()=2
When the expected result is the same for both methods.
When looking at the obfuscated code with the IntelliJ IDEA decompiler, the difference is obvious :
method1 :
b var10000 = this.a;
Objects.requireNonNull(var10000);
b var1 = var10000;
byte var2 = 0;
switch (var1.typeSwitch<invokedynamic>(var1, var2)) {
...
}method2 :
switch (((a)this.a).ordinal()) {
...
}