Java中如何对字符串进行utf-8编码

// 使用 URLEncoder 库对字符串进行 utf-8 编码
import java.net.URLEncoder;

public String encodePathVariable(String pathVariable) {
   String ret = "default";
    try {
        ret = URLEncoder.encode(pathVariable, "utf-8");
        System.out.println(pathVariable + " : " + ret);
    }catch(Exception e) {
        System.out.println(e);
    }
    return ret;
}

public static String getFromCompressedUnicode(String string,int offset,int len) throws UnsupportedEncodeingException{
byte[] bytes = string.getBytes("utf-8");
int len_to_use = Math.min(len,bytes.length - offset);
 return new String(bytes,offset,len_to_use,"utf-8").replaceAll("�","")
}