0x001 算数运算符

? 1 2 3 4 5 6 int num1 = 1, num2 = 2; system.out.println(num1 + num2); // 3 system.out.println(num1 - num2); // -1 system.out.println(num1 / num2); // 0 system.out.println(num1 * num2); // 2 system.out.println(num1 % num2); //1

0x002 自增自减

? 1 2 3 4 5 6 system.out.println(num1++); // 1 system.out.println(num1); // 2 system.out.println(num1--); // 2 system.out.println(num1); // 1 system.out.println(++num1); // 2 system.out.println(--num1); // 1

0x003 关系操作符

? 1 2 3 4 system.out.println((num1 < num2)); // true system.out.println((num1 > num2)); // false system.out.println(num1 == num2); // false system.out.println(num1 != num2); // true

0x004 逻辑操作符

? 1 2 3 4 5 boolean boolean1 = false; boolean boolean2 = true; system.out.println(boolean1 && boolean2); // false system.out.println(boolean1 || boolean2); // true system.out.println(!boolean1); // true

0x005 直接操作符

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 int i1 = 0x2f; int i2 = 0x2f; int i3 = 0177; char c1 = 0xffff; byte b1 = 0x7f; short s1 = 0x7f; long l1 = 100l; long l2 = 100l; float f1 = 1; float f2 = 1f; float f3 = 1f; double d1 = 1d; double d2 = 1d; system.out.println(i1); // 47 system.out.println(i2); //47 system.out.println(i3); // 127 system.out.println(c1); // system.out.println(b1); // 127 system.out.println(s1); // 127 system.out.println(l1); // 100 system.out.println(l2); // 100 system.out.println(f1); // 1.0 system.out.println(f2); // 1.0 system.out.println(f3); // 1.0 system.out.println(d1); // 1.0 system.out.println(d2); // 1.0

0x006 三元运算符

? 1 2 3 4 int a = 0; boolean issuccess = false; a = issuccess ? 1 : 2; system.out.println(a);// 2

0x007 字符串+、+=

? 1 2 3 4 string str = ""; str = str + "1"; str += "2"; system.out.println(str);

0x008 类型转化

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 int i = 100; long long1 = (long) i; system.out.println(long1);// 100 long1 = i; system.out.println(long1);// 100 long long2 = (long) 200; system.out.println(long2);// 200 i = (int) long1; system.out.println(i); // 200 float float1=0.1f; float float2=0.9f; system.out.println((int) float1);// 转化int会被舍去 system.out.println((int) float2);// 转化int会被舍去