Java case关键字
Java case关键字是与switch语句一起使用的条件标签。它包含一个代码块，仅当开关值与大小写匹配时才执行。
switch语句可以包含多个大小写标签。每个案例标签必须具有不同的值。案例标签可以包含break语句，该语句终止执行流程。
注意: 该案例不包含布尔，浮点和双精度类型的值。
语法
switch(expression){
case value1:
//code to be executed;
break; //optional
case value2:
//code to be executed;
break; //optional
default:
code to be executed if all cases are not matched;
}
Java case关键字的示例
示例1: 包含字符串值的case标签
public class caseExample1 {
public static void main(String[] args) {
String week = "Monday";
switch (week) {
case "Monday":
System.out.println("Monday");
}
}
}
输出:
示例2: 多个案例标签
public class caseExample2 {
public static void main(String[] args) {
String week = "Monday";
switch (week) {
case "Monday":
System.out.println("Monday");
break;
case "Tuesday":
System.out.println("Tuesday");
break;
case "Wednesday":
System.out.println("Wednesday");
break;
case "Thursday":
System.out.println("Thursday");
break;
case "Friday":
System.out.println("Friday");
break;
case "Saturday":
System.out.println("Saturday");
break;
case "Sunday":
System.out.println("Sunday");
break;
default:
System.out.println("default");
}
}
}
输出:
示例3: 大小写标签包含int值
public class caseExample3 {
public static void main(String[] args) {
int num = 20;
switch (num) {
case 10:
System.out.println("The number is 10");
break;
case 20:
System.out.println("The number is 20");
break;
case 30:
System.out.println("The number is 30");
break;
default:
System.out.println("default");
}
}
}
示例4: 案例标签中包含switch语句
public class caseExample4 {
public static void main(String[] args) {
String college_name = "BIT";
int department_id = 102;
switch (college_name) {
case "BIT":
System.out.println("BIT");
switch (department_id) {
case 101:
System.out.println("Mechanical Department");
break;
case 102:
System.out.println("Computer Department");
break;
case 103:
System.out.println("Civil Department");
break;
}
break;
case "ITS":
System.out.println("ITS");
switch (department_id) {
case 101:
System.out.println("Mechanical Department");
break;
case 102:
System.out.println("Computer Department");
break;
case 103:
System.out.println("Civil Department");
break;
}
break;
case "ABS":
System.out.println("ABS");
switch (department_id) {
case 101:
System.out.println("Mechanical Department");
break;
case 102:
System.out.println("Computer Department");
break;
case 103:
System.out.println("Civil Department");
break;
}
break;
default:
System.out.println("default");
}
}
}
输出:
