/* 1 ( 最快 ) */

for (int i = initializer; i >= 0; i--) { ... }

/* 2 第二 */

int limit = calculateLoopLimit();

for (int i = 0; i < limit; i++) { ... }

/* 3 */

Type[] array = getMyArray();

for (Type obj : array) { ... } /* 4 */ for (int i = 0; i < array.length; i++) { ... }

/* 5 */

for (int i = 0; i < this.var; i++) { ... }

/* 6 */

for (int i = 0; i < obj.size(); i++) { ... }

/* 7 (最慢) */

Iterable<Type> list = getMyList();

for (Type obj : list) { ... }