usage of stringbuffer length.

[sowmya vasisht]

Hi,
Can anybody help me in knowing how to truncate Stringbuffer elements when it exceeds some predetermined legnth without loosing data.
first in a while loop of vector i m appending the account number, then the account status to a string buffer. but when the length of the string buffer exceeds a predetermined length, for eg., if the legnth has to be 400, then if the addition of accoutn number and status is more than 400 then it should remove the last added number and status. and pass the data which is less than 400 or equal to.
Could anybody tel me how to go about it??
thanx in advance.
sowmya

[Michael Morris]

Hi sowmya,
You can try something like this:

public class TruncateBuffer {
    private StringBuffer buff;
    private int buffSize;
    public TruncateBuffer(int buffSize) {
        this.buffSize = buffSize;
        clearBuffer();
    }
    public StringBuffer getBuffer() {
        return buff;
    }
    public boolean willOverflowBuffer(String string) {
        return ((string.length() + buff.length()) > buffSize);
    }
    public void clearBuffer() {
        buff = new StringBuffer();
    }
    public static void main(String[] args) {
        TruncateBuffer buff = new TruncateBuffer(40);
        String[] str = {"This is a test of the TruncateBuffer",
                        " class. ",
                        "If this works, ",
                        "then all",
                        "lines should be less than or equal",
                        " to forty characters.",
                        " Testing, 1, 2, 3" };
       for (int i = 0; i < str.length; i++) {
           if (buff.willOverflowBuffer(str[i])) {
               System.out.println(buff.getBuffer().toString());
               buff.clearBuffer();
           }
           buff.getBuffer().append(str[i]);
       }
       System.out.println(buff.getBuffer().toString());
   }
}

Hope this helps,
Michael Morris