一个IO流程序的问题 - 黑马程序员技术交流社区

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FilenameFilter;
import java.io.InputStream;
import java.io.SequenceInputStream;
import java.util.Enumeration;
import java.util.Vector;
public class StreamTest {
public static void main(String[] args) throws Exception {
Vector<InputStream> vector = new Vector<>();
File dir = new File("E:\\nihao");
File[] files = dir.listFiles(new FilenameFilter() {
public boolean accept(File dir, String name) {
return name.endsWith(".txt");
}
});
for (File file : files) {
vector.add(new FileInputStream(file));
}
Enumeration<InputStream> enumeration = vector.elements();
SequenceInputStream stream = new SequenceInputStream(enumeration);
FileOutputStream fos = null;
int i = 1;
int len = -1;
int total = 0;
byte[] buf = new byte[20];
while ((len = stream.read(buf, total, buf.length - total)) != -1) {
total += len;
if (total == buf.length) {
fos = new FileOutputStream("E:\\nihao\\" + i++ + ".txt");
fos.write(buf, 0, total);
total = 0;
}
}
// 读完的最后一次可能不足buf.length个字节。需要单独处理
fos = new FileOutputStream("E:\\nihao\\" + i + ".txt");
fos.write(buf, 0, total);
}
}

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import java.io.*;
import java.util.*;
public class StreamTest {
/**
* @param args
*/
public static void main(String[] args) throws Exception
{
getFile("W:\\javawork\\bxd\\day25");
}
public static void getFile(String str) throws Exception
{
Vector<InputStream> v = new Vector<InputStream>();
File f = new File(str);
FileInputStream fis = null;
FileOutputStream fos = null;
// 获取此文件目录下所有的txt文件
String[] fileNames = f.list(new FilenameFilter()
{
public boolean accept(File f, String name)
{
return name.endsWith(".java");
}
});
for (String fileName : fileNames)
{
fis = new FileInputStream(str + "\\" + fileName);
v.add(fis);
}
Enumeration<InputStream> e = v.elements();
SequenceInputStream se = new SequenceInputStream(e);
byte[] by = new byte[450];
int len = 0;
//以上部分都一样，下边的与楼主不同不同。
int num = 0;//记录读取的所有文件的总长
int num1 = 0;//记录当前操作文件已写入的字符长度。
int pos = 0;//当前操作文件需要写入的字符长度。
int i = 1;//文件标题自增计数器
fos=new FileOutputStream((str+"\\"+(i++)+".txt"));
while ((len = se.read(by)) != -1)
{
System.out.println("len="+len);
num=num+len;
while(len>0)
{
pos = by.length-num1;
if(len<pos)
{
fos.write(by,0,len); //写入后，写入计数器增加，len清空
num1+=len;
len=0;
}
else//len>=pos的情况。
{
fos.write(by,0,pos);//写入后，写入计数器归零，len减去写入的长度。
num1 = 0;
len -= pos;
System.out.println("pos="+pos+" num1="+num1+" i="+i);
fos.close();
fos=new FileOutputStream((str+"\\"+(i++)+".txt"));
}
}
}
fis.close();
fos.close();
}
}

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