effect of changing String using reflection

Question

As we all know, String is immutable in java. however, one can change it using reflection, by getting the Field and setting access level. (I know it is unadvised, I am not pl

Answer 1

To demonstrate how can it screw up a program:

System.out.print("Initial: "); System.out.println(addr);
editIntStr("ADDR_PLACEH", "192.168.1.1");
System.out.print("From var: "); System.out.println(addr);//
System.out.print("Hardcoded: "); System.out.println("ADDR_PLACEH");
System.out.print("Substring: "); System.out.println("ADDR_PLACE" + "H".substring(0));
System.out.print("Equals test: "); System.out.println("ADDR_PLACEH".equals("192.168.1.1"));
System.out.print("Equals test with substring: ");  System.out.println(("ADDR_PLACE" + "H".substring(0)).equals("192.168.1.1"));

Output:

Initial: ADDR_PLACEH
From var: 192.168.1.1
Hardcoded: 192.168.1.1
Substring: ADDR_PLACEH
Equals test: true
Equals test with substring: false

The result of the first Equals test is weird, isn't it? You can't expect your fellow programmers to figure out why is Java thinking they are equal...
Full test code: http://pastebin.com/vbstfWX1