怎样用java合并多个文件 - 黑马程序员技术交流社区

package mysql;
import static java.lang.System.out;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.Arrays;
public class merge {
public static final int BUFSIZE = 1024 * 8;
public static void mergeFiles(String outFile, String[] files) {
FileChannel outChannel = null;
//out.println("Merge " + Arrays.toString(files) + " into " + outFile);
try {
outChannel = new FileOutputStream(outFile).getChannel();
for(String f : files){
FileChannel fc = new FileInputStream(f).getChannel();
ByteBuffer bb = ByteBuffer.allocate(BUFSIZE);
while(fc.read(bb) != -1){
bb.flip();
outChannel.write(bb);
bb.clear();
}
fc.close();
}
//out.println("Merged!! ");
} catch (IOException ioe) {
ioe.printStackTrace();
} finally {
try {if (outChannel != null) {outChannel.close();}} catch (IOException ignore) {}
}
}
public static void main(String[] args) {
mergeFiles("f:/ex/output.txt", new String[]{"f:/ex/new.txt","f:/ex/new1.txt"});
}
}

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package test;
import java.io.*;
import java.util.*;
public class Test6
{
public static void main(String[] args) throws Exception
{
String s = "D:/out.mp3"; // 输出目录 & 文件名
List<String> list = new ArrayList<String>();
File dir = new File("D:/aaa"); // 要遍历的目录, 用递归拿文件,文件太多就完蛋.
recursion(dir.listFiles(), list); // 递归函数
String[] ss = new String[list.size()];
for (int i = 0; i < ss.length; i++)
{
ss[i] = list.get(i);
}
System.out.println();
combine(s, ss);
}
public static void recursion(File[] fs, List<String> list) // 递归得所有子目录的.mp3文件.
{
for (File f : fs)
{
if (f.isDirectory())
{
recursion(f.listFiles(), list);
}
else
{
if (f.getName().endsWith(".mp3"))
{
list.add(f.getAbsolutePath());
}
}
}
}
private static boolean combine(String outFile, String[] inFiles) throws Exception
{
File out = new File(outFile);
File[] files = new File[inFiles.length];
for (int i = 0; i < files.length; i++)
{
files[i] = new File(inFiles[i]);
}
FileInputStream fis = null;
FileOutputStream fos = new FileOutputStream(outFile, true); // 合并其实就是文件的续写,写成true
for (int i = 0; i < files.length; i++)
{
fis = new FileInputStream(files[i]);
int len = 0;
for (byte[] buf = new byte[1024 * 1024]; (len = fis.read(buf)) != -1;)
{
fos.write(buf, 0, len);
}
}
fis.close();
fos.close();
return true;
}
}

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