java--流程控制
1. if条件语句
if (logic expression){ statement... } else if (logic expression){ statement... } else { statement... }
2. switch分支语句
switch (expression){ case condition1:{ statement(s) break; } case condition2:{ statement(s) break; } ... case conditionN:{ statement(s) break; } default:{ statement(s) } }
switch的运行机制是, 根据值找到对应的那一行, 然后向后执行, 直到遇到break为止
expression表达式的数据类型只能是 byte, short, char, int, String和枚举类型
3. 循环结构
[init_statement] while (test_expression){ statement; [iteration_statement]
}
[init_statement] do{ statement; [iteration_statement] }while (test_expression);
[outer:] for ([init_statement]; [test_expression]; [iteration_statement]){ statement [continue; //结束本次循环开始下次循环] [break; //结束循环] for (...){ statement [break outer; //跳出外层循环] } }
for (type variableName : array | collection){ // variableName自动迭代访问每个元素 }