import java.io.*;
import java.lang.*;
public class AppendStringTest { public static void main(String[] args) {
StringBuilder builder = new StringBuilder(" ");
}}到底要用那个库阿???
StringBuilder难道不是这样用么
import java.lang.*;
public class AppendStringTest { public static void main(String[] args) {
StringBuilder builder = new StringBuilder(" ");
}}到底要用那个库阿???
StringBuilder难道不是这样用么
有啥错误提示?
public class AppendStringTest { public static void main(String[] args) {
StringBuilder builder = new StringBuilder(" 123"); System.out.println(builder);
}}
方法二:
import java.lang.StringBuffer;
public class AppendStringTest { public static void main(String[] args) {
StringBuffer buffer = new StringBuffer(" 123"); System.out.println(builder);
}}