Infinite Loops in Java: while(true) vs for(;;) – Which Is Better?

Sometimes we write loops that exit based on a condition rather than a fixed iteration count, leading to patterns like:

while (true)

for (;;)

The question arises: which form is better?

The discussion references a Zhihu answer that analyzes these two styles.

mymbp:/Users/me/workspace/jdk8u/jdk/src
$ egrep -nr "for \(\s?;\s?;" . | wc -l
      369
mymbp:/Users/me/workspace/jdk8u/jdk/src
$ egrep -nr "while \(true" . | wc -l
      323

The counts show no significant difference.

The for (;;) style originates from C, where writing while(1) without a boolean literal was common; however, many developers dislike the magic number 1. Using for (;;) expresses an infinite loop without any condition or magic number, making it visually clear.

In Java, the author prefers while (true) but accepts for (;;) in other projects.

Regarding performance, the Java language specification does not dictate which is faster; it depends on the implementation. Examining the bytecode generated by javac for both forms in Oracle/Sun JDK8u shows they compile to identical bytecode.

public void foo() {
    int i = 0;
    while (true) { i++; }
}
/*
  public void foo();
    Code:
      stack=1, locals=2, args_size=1
         0: iconst_0
         1: istore_1
         2: iinc          1, 1
         5: goto          2
*/

public void bar() {
    int i = 0;
    for (;;) { i++; }
}
/*
  public void bar();
    Code:
      stack=1, locals=2, args_size=1
         0: iconst_0
         1: istore_1
         2: iinc          1, 1
         5: goto          2
*/

Since both compile to the same bytecode, there is no performance difference at the source level; any further differences would depend on JIT compilation and runtime optimizations, which treat them identically.