Java 常见异常lllegalArgumentException

lllegalArgumentException

java.lang.lllegalArgumentException是非法参数异常，迪常是调用方法时引发的异常。当给一个 方法传递的参数与实际定义不相符时，会拋出lllegalArgumentException异常。

import java.io.File;

//NumberFormatException

public class Demo {

public static String createFilePath(String parent, String filename) throws IllegalArgumentException{ 

if (parent == null)

throw new IllegalArgumentException("文件路径不能为空！ "); 

if(filename == null)

throw new IllegalArgumentException("文件名称不能为空！ ");

return parent + File.separator + filename;

}

public static void main(String[] args) {

System.out.println(Demo.createFilePath("dir1" ,"file1"));

System.out.println();

System.out.println(Demo.createFilePath(null, "file1"));

}

}