Question

有没有办法简化这个代码，可能会像写作然后变量然后再写一样？我的意思是一条线。

class tests {
public static void main(String args[]) {
    int david, mark, alex;
    david = 20;
    mark = 30;
    alex = 12;

        System.out.println("hey");
    System.out.print("I can't believe that mark is ");
    System.out.print(mark);
    System.out.print(" years old.. thank god alex and david are  ");
    System.out.print(alex);
    System.out.print(" and ");
    System.out.print(david);
    System.out.print("...");
 }

}

请注意，编写简单的东西需要多少System.out.print？无论如何还是要使用这些变量来简化这个吗？

Answer 1

你可以这样做：

System.out.println("hey\n I can't believe that mark is "+mark+" years old.. thank god alex and david are  "+alex+" and "+david+"...");

注意，因为您使用println（表示新行）“hey”，您需要在其中添加\n < / p>

Answer 2

System.out.printf("hey%n I can't believe that mark is %s years old.. thank god alex and david are  %s and %s...",mark,alex,david);

Answer 3

喜欢这个

StringBuilder sb = new StringBuilder();
sb.append("hey");
sb.append("\n");
sb.append("I can't believe that mark is ");
sb.append(mark);
sb.append(" years old.. thank god alex and david are  ");
sb.appendt(alex);
sb.append(" and ");
sb.append(david);
sb.append("...");
System.out.println(sb.toString());

如果您执行以下代码，则会给您带来很少的性能问题。

System.out.println("hey\n I can't believe that mark is "+mark+" years old.. thank god alex and david are  "+alex+" and "+david+"...");

每个'+'操作它将创建新的String对象。

使用StringBuilder进行字符串连接操作。您可以根据需要将更多字符串附加到StringBuilder。如果你想清除StringBuilder，请使用myStringBuilder.setLength（0）;或者创建新的StringBuilder对象。

Answer 4

在此方案中使用 String.format 方法。

int x = 10;
String name = "User1";

String result = String.format("Hi %s, this is your number %d",name,x);
System.out.println(result);

感谢。

Answer 5

这样做

StringBuilder sb = new StringBuilder();
sb.append("hey\n").append("I can't believe that mark is ").append(mark).append(" years old.. thank god alex and david are  ").append(alex).append(" and ").append(david).append("...");

System.out.print(sb.toString());

出于性能原因，你真的不想使用“+”连接很多字符串。

你能把变量写进去吗？详情请见

5 个答案: