Java 字符终端上获取输入三种方式(二)
入输出重定向到了 IDE 的控制台中
public class TestConsole3 {
public static void main(String[] args) {
String str = readDataFromConsole("Please input string:");
System.out.println("The information from console:" + str);
}
/**
* Use java.io.console to read data from console
*
* @param prompt
*
* @return input string
*/
private static String readDataFromConsole(String prompt) {
Console console = System.console();
if (console == null) {
throw new IllegalStateException("Console is not available!");
}
return console.readLine(prompt);
}
}
Console类还有个特色就是，专门对密码(输入无回显)等安全字符，进行了处理。专门提供 readPassword()方法,具体应用见如下代码：
public class TestConsole5 {
public static void main(String[] args) {
Console console = System.console();
if (console == null) {
throw new IllegalStateException("Console is not available!");
}
while(true){
String username = console.readLine("Username: ");
char[] password = console.readPassword("Password: ");
if (username.equals("Chris") && String.valueOf(password).equals("GoHead")) {
console.printf("Welcome to Java Application %1$s.\n", username);
// 使用后应立即将数组清空，以减少其在内存中占用的时间，增强安全性
password = null;
System.exit(-1);
}
else {
console.printf("Invalid username or password.\n");
}
}
}
}