The local variable is not initialized, but the program still compiles

Question

public class Test {

   public static void main(String[] args) {
       System.out.println("started");
       //func();

   }

   static void func(){
       double d;
       int i;
       System.out.println("d ="+d);
       System.out.println("i ="+i);
   }

}

What I know are local variables that must be initialized before they are used. Here dand iare local variables. You can see that I did not initialize them. Why can I still compile the program and execute it?

If I disable func (), I get a compilation error.

Answer 1

If you use javacto compile it, it does not compile:

stephen@blackbox tmp]$ cat > Test.java
public class Test {

   public static void main(String[] args) {
       System.out.println("started");
       //func();

   }

   static void func(){
       double d;
       int i;
       System.out.println("d ="+d);
       System.out.println("i ="+i);
   }

}
[stephen@blackbox tmp]$ javac Test.java 
Test.java:12: error: variable d might not have been initialized
       System.out.println("d ="+d);
                                ^
Test.java:13: error: variable i might not have been initialized
       System.out.println("i ="+i);
                                ^
2 errors
[stephen@blackbox tmp]$ 

---

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Answer 2

. :

Test.java:12: error: variable d might not have been initialized
   System.out.println("d ="+d);
                            ^
Test.java:13: error: variable i might not have been initialized
   System.out.println("i ="+i);
                            ^
2 errors