Java String 使用空格和零右填充字符串

在本教程中，我们将看到如何正确填充带空格和零的字符串：

使用空格右填充

public class PadRightExample1 {
  public static void main(String[] argv) {
    System.out.println("#" + rightPadding("mystring", 10) + "@");
    System.out.println("#" + rightPadding("mystring", 15) + "@");
    System.out.println("#" + rightPadding("mystring", 20) + "@"); 
  }

  public static String rightPadding(String str, int num) {
    return String.format("%1$-" + num + "s", str);
  }
}

输出：

#mystring  @
#mystring       @
#mystring            @

使用零右填充

public class PadRightExample2 {
  public static void main(String[] argv) {
    System.out.println("#" + rightPadZeros("mystring", 10) + "@");
    System.out.println("#" + rightPadZeros("mystring", 15) + "@");
    System.out.println("#" + rightPadZeros("mystring", 20) + "@");
  }

  public static String rightPadZeros(String str, int num) {
    return String.format("%1$-" + num + "s", str).replace(' ', '0');
  }
}

输出：

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