public java.lang.StringBuffer append(char[] str,int offset,int len){
  internal.append(str,offset,len);
  return this;
}

public java . lang . StringBuffer append ( char [ ] str , int offset , int len ) { internal . append ( str , offset , len ) ; return this ; }
appends the string representation of a subarray of the char array argument to this string buffer . characters of the character array str , starting at index offset , are appended , in order , to the contents of this string buffer . the length of this string buffer increases by the value of len . the overall effect is exactly as if the arguments were converted to a string by the method string . valueof ( char [ ] , int , int ) and the characters of that string were then appended to this stringbuffer object .
