numberlenghtlimiteddmt.java

accp s1毕业项目 考试管理系统

package com.exam.ui.manage;

import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;

public class NumberLenghtLimitedDmt extends PlainDocument {
	private static final long serialVersionUID = 1L;
	private int limit;

	public NumberLenghtLimitedDmt(int limit) {
		super();
		this.limit = limit;
	}

	public void insertString(int offset, String str, AttributeSet attr)
			throws BadLocationException {
		if (str == null) {
			return;
		}
		if ((getLength() + str.length()) <= limit) {
			char[] upper = str.toCharArray();
			int length = 0;
			for (int i = 0; i < upper.length; i++) {
				if (upper[i] >= '0' && upper[i] <= '9') {
					upper[length++] = upper[i];
				}
			}
			super.insertString(offset, new String(upper, 0, length), attr);
		}
	}
}