package aa;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.FileInputStream;
import java.io.FileOutputStream;
public class Util {
public Util() {
}
public static byte[] readFile(String filename) throws IOException {
File file = new File(filename);
if (filename == null || filename.equals("")) {
throw new NullPointerException("无效的文件路径");
}
long len = file.length();
byte[] bytes = new byte[(int) len];
BufferedInputStream bufferedInputStream = new BufferedInputStream(new
FileInputStream(file));
int r = bufferedInputStream.read(bytes);
if (r != len) {
throw new IOException("读取文件不正确");
}
bufferedInputStream.close();
return bytes;
}
public byte[] readFileJar(String filename) throws IOException {
BufferedInputStream bufferedInputStream = new BufferedInputStream(
getClass().getResource(filename).openStream());
System.out.println(filename);
int len = bufferedInputStream.available();
byte[] bytes = new byte[len];
int r = bufferedInputStream.read(bytes);
if (len != r) {
bytes = null;
throw new IOException("读取文件不正确");
}
bufferedInputStream.close();
return bytes;
}
public static void main(String[] args) {
Util util = new Util();
try {
util.readFile("D:\\XiaoFei\\aaaaaa.txt");
util.readFileJar("D:\\XiaoFei\\aaaaaa.txt");
} catch (IOException ex) {
}
}
}
这是代码!
以下是错误提示:
java.lang.NullPointerException
at aa.Util.readFileJar(Util.java:35)
at aa.Util.main(Util.java:54)
Exception in thread "main"
报错位置:
BufferedInputStream bufferedInputStream = new BufferedInputStream(
getClass().getResource(filename).openStream());
util.readFileJar("D:\\XiaoFei\\aaaaaa.txt");
不知道是什么错误!!!!求高手解决~
------解决方案--------------------------------------------------------
用文件流试试
------解决方案--------------------------------------------------------
getClass().getResource(filename)这个是要干啥？
------解决方案--------------------------------------------------------
原先的getClass().getResource(filename).openStream() 返回的是null
所以报空指针错误
修改为：
BufferedInputStream bufferedInputStream = new BufferedInputStream(
new FileInputStream(filename));
再试试
------解决方案--------------------------------------------------------
你要这样getClass().getResource(filename)用的话
file必须要在package里，不能用d:\\...访问，要用相对路径
------解决方案--------------------------------------------------------
lz应该去看class getResource()的相关内容 其实目前这个问题算是个classpath的问题