JAVA 将汉语转为unicode

public?String?chinaToUnicode(String?str){?

/***?中文转?unicode?***/
String?result="";
int?len=str.length();
for(int?i=0;i<len;i++){
????????????int?chr1=(char)str.charAt(i);
????????????if(chr1>=19968&&chr1<=171941){
????????????????result+="?\\u"+Integer.toHexString(chr1);
????????????}else{
???????????? result+=str.charAt(i);
????????????}
????????}
return?result;
}