运行结果：请输入需要压缩的第1文件的文件名:
a.txt
Exception in thread "main" java.lang.NullPointerException
at Zip.zip(Zip.java:19)
at Main.main(Main.java:8)
是否还需要输入文件？yes/no
不知道怎么解决了请高手指点。。谢谢。。
源代码：
//功能函数
import java.io.*;
import java.util.zip.*;
public class Zip {
void zip() throws IOException{
BufferedReader in1;
in1 = new BufferedReader(new InputStreamReader(System.in));
String cs = null;
String[] file;
int i = 0;
do {
System.out.println("请输入需要压缩的第"+(i+1)+"文件的文件名:");
file=new String[i+1];
file[i]=in1.readLine();
i++;
System.out.println("是否还需要输入文件？yes/no");
} while (cs.equals("yes"));
in1.close();
ZipOutputStream out1;
out1 = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream("b.zip")));
for (int j = 0; j <file.length; j++) {
BufferedInputStream in2;
in2 = new BufferedInputStream(new FileInputStream(file[j]));
out1.putNextEntry(new ZipEntry(file[j]));
int c = 0;
while ((c = in2.read()) != -1) {
out1.write(c);
}
in2.close();
}
out1.close();
}
}
//主函数
import java.io.IOException;
public class Main {
public static void main(String[] args) throws IOException {
Zip zp = new Zip();
zp.zip();
}
}
------解决方案--------------------
你的：
do {
System.out.println("请输入需要压缩的第"+(i+1)+"文件的文件名:");
file=new String[i+1];file[i]=in1.readLine();
i++;
System.out.println("是否还需要输入文件？yes/no");
} while (cs.equals("yes"));
in1.close();
是不对的，
其实到循环结束，你只读到了最后一个文件，而且数组的前几项都是空的，
在后面压缩的时候肯定会包空指针异常
------解决方案--------------------
- Java code
void zip() { BufferedReader in1=new BufferedReader(new InputStreamReader(System.in)); String[] file=null; try { System.out.print("请输入压缩包数量："); int sum=Integer.parseInt(in1.readLine()); file = new String[sum]; int i = 0; do { System.out.println("请输入需要压缩的第"+(i+1)+"文件的文件名:"); file[i]=in1.readLine(); i++; } while (i<=sum-1); } catch (IOException e) { e.printStackTrace(); } finally{ try { if(null!=in1){ in1.close(); } } catch (IOException e) { e.printStackTrace(); } } ZipOutputStream out1 = null; BufferedInputStream in2 = null; try { for (int j = 0; j <file.length; j++) { out1 = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream(file[j]+j+"_b.zip"))); in2 = new BufferedInputStream(new FileInputStream(file[j])); byte[] temp=new byte[in2.available()]; out1.putNextEntry(new ZipEntry(file[j])); in2.read(temp); out1.write(temp); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally{ try { if(null!=in2){ in2.close(); } if(null!=out1){ out1.close(); } System.out.println("文件另外压缩复制完成！"); } catch (IOException e) { e.printStackTrace(); } } }