utils.java

来自「java图形用户界面 6.1 HelloWorldSwing 6.2 按钮计」· Java 代码 · 共 20 行

import java.io.File;

public class Utils {
    public final static String jpeg = "jpeg";
    public final static String jpg = "jpg";
    public final static String gif = "gif";
    public final static String tiff = "tiff";
    public final static String tif = "tif";
      //获取文件后缀名.
    public static String getExtension(File f) {
        String ext = null;
        String s = f.getName();
        int i = s.lastIndexOf('.');
        if (i > 0 &&  i < s.length() - 1) {
            ext = s.substring(i+1).toLowerCase();
        }
        return ext;
    }
}