小知识，大挑战！本文正在参与「程序员必备小知识」创作活动

🔥 Android Studio 自动补全

💥 判断为空

变量.null+Enter

注意：只要 if (expr == null) 出现就可以 enter(回车) 了。其他相同

        int []a = {1,2,3,4,5};
        if (a == null) {
            
        }

💥 判断非空

变量.notnull+Enter

变量.nn+Enter(简单版)

        int []a = {1,2,3,4,5};
        if (a != null) {
            
        }

💥 本身for循环

变量.for+Enter

        int []a = {1,2,3,4,5};
        for (int i : a) {
            
        }

💥 变量for循环

变量.fori+Enter

        int []a = {1,2,3,4,5};
        for (int i = 0; i < a.length; i++) {
            
        }

💥 变量倒序for循环

变量.forr+Enter

        int []a = {1,2,3,4,5};
        for (int i = a.length - 1; i >= 0; i--) {
            
        }

💥 加括号

变量.arg+Enter

        int []a = {1,2,3,4,5};
        (a)

💥 if判断

判断语句.if+Enter

        int []a = {1,2,3,4,5};
        if (a.length>3) {
            
        }

💥 快速定义变量

变量.var+Enter

        String str = "str";
        int i = 520;

💥 强制转换

变量.cast+Enter

        int i = 520;
        (double) i

💥 变量承接强转

变量.castvar+Enter

        int i = 520;
        double doubl = (double) i;

💥 返回函数

变量.return+Enter

    private int getNumber(){
        return 520;
    }

💥 switch

变量.switch+Enter

        int i = 520;
        switch (i) {
            
        }

💥 try

变量.try+Enter

        int i = 520;
        try {
            i
        } catch (Exception e) {
            e.printStackTrace();
        }

💥 输出

sout

变量.sout

变量.soutv

变量.souf

        int i = 520;
        System.out.println(i==3);
        System.out.println(i);
        System.out.println("i = " + i);
        System.out.printf("", i);