Java Compiler: Stop complaining about dead code

Question

For testing purposes, I often start typing some code in an already existing project. So, my code I want to test comes before all the other code, like this: ``` public static void main(String[] args) { char a = '%'; System.out.println((int)a); // To know where '%' is located in the ASCII table. // But, of course, I don't want to start the whole project, so: return; // The real project starts here... } ``` But the compiler complains about the `return`-statement, because of the following "dead code". (While in C++ the compiler obeys the programmer and simply compiles the return statement) To prevent the compiler complains, I write a stupid `if`-statement: ``` if (0 != 1) return; ``` I hate it. Why can't the compiler do what I ask? Are there some compilation flags or annotations or whatever to solve my problem? Thanks

Accepted Answer

There are no flags to turn of this behaviour. The rules that make dead code a compile time error are part of the JLS (§14.21 Unreachable Statements) and can't be turned off.

There's an explicit loophole in the loop which allows code like this:

```
if (true) return;

someOtherCode(); // this code will never execute, but the compiler will still allow it
```

This is done explicitly to allow "commenting-out" or conditional compilation (depending on some `static final boolean` flag).

In case you're curious: the loophole is based on the fact that a known-constant value of the condition expression of an `if` statement is not considered when checking reachability of code within or after the `if` statement. A similar situation occurs with `while`, where known-constant values are considered, so this code will not compile:

```
while (true) return;

someOtherCode(); // this will be flagged as an unreachable statement
```

Java Compiler: Stop complaining about dead code

Solution

Problem