java合并文件

Ⅰ 如何使用java合并多个文件

使用java编程语言，对文件进行操作，合并多个文件，代码如下：

importstaticjava.lang.System.out;
importjava.io.FileInputStream;
importjava.io.FileOutputStream;
importjava.io.IOException;
importjava.nio.ByteBuffer;
importjava.nio.channels.FileChannel;
importjava.util.Arrays;

publicclasstest{

publicstaticfinalintBUFSIZE=1024*8;

publicstaticvoidmergeFiles(StringoutFile,String[]files){
FileChanneloutChannel=null;
out.println("Merge"+Arrays.toString(files)+"into"+outFile);
try{
outChannel=newFileOutputStream(outFile).getChannel();
for(Stringf:files){
FileChannelfc=new尘李FileInputStream(f).getChannel();
芹碰ByteBufferbb=ByteBuffer.allocate(BUFSIZE);
while(fc.read(bb)!=-1){
bb.flip();
outChannel.write(bb);
bb.clear();
}
fc.close();
}
out.println("Merged!!");
嫌兄谈}catch(IOExceptionioe){
ioe.printStackTrace();
}finally{
try{if(outChannel!=null){outChannel.close();}}catch(IOExceptionignore){}
}
}
//下面代码是将D盘的1.txt2.txt3.txt文件合并成out.txt文件。
publicstaticvoidmain(String[]args){
mergeFiles("D:/output.txt",newString[]{"D:/1.txt","D:/2.txt","D:/3.txt"});
}
}

Ⅱ java合并两个txt文件并生成新txt

importjava.io.File;
importjava.io.FileNotFoundException;
importjava.io.PrintStream;
importjava.util.Arrays;
importjava.util.Collections;
importjava.util.LinkedList;
importjava.util.Scanner;

publicclassTest
{
	publicstaticfinalStringLINE=System.getProperty("line.separator");

	publicstaticint[]readfile(Scannerinput)
	{
		int[]a=newint[0];
		while(input.hasNextLine())
		{
			Stringline=input.nextLine().trim();
			int[]dest=newint[a.length+1];
			System.array(a,0,dest,0,a.length);
			dest[dest.length-1]=Integer.parseInt(line);
			a=dest;
		}
		input.close();
		returna;
	}

	publicstaticvoidwritefile(PrintStreamoutput,int[]a)
	{
		output.append(Arrays.toString(a).replaceAll("[\[\]\s]","").replaceAll(",",LINE));
		output.flush();
		output.close();
	}

	publicstaticint[]merge(int[]a,int[]b)
	{
		int[]dest=newint[a.length+b.length];
		System.array(a,0,dest,0,a.length);
		System.array(b,0,dest,a.length,b.length);
		returndest;
	}
}

classTest1
{
	publicstaticvoidmain(String[]args)
	{
		if(args.length!=3)
		{
			System.err.println("输入的参数个数不是3个");
			return;
		}
		try
		{
			Scannerinput=newScanner(newFile(args[0]));
			int[]a=Test.readfile(input);
			input=newScanner(newFile(args[1]));
			int[]b=Test.readfile(input);
			int[]dest=Test.merge(a,b);
			try
			{
				PrintStreamoutput=newPrintStream(args[2]);
				Test.writefile(output,dest);
			}
			catch(FileNotFoundExceptione)
			{
				e.printStackTrace();
			}
		}
		catch(FileNotFoundExceptione)
		{
			e.printStackTrace();
		}
	}
}

classTest2
{
	publicstaticvoidmain(String[]args)
	{
		if(args.length!=1)
		{
			System.err.println("输入的参数个数不是1个");
			return;
		}
		try
		{
			Scannerinput=newScanner(newFile(args[0]));
			int[]dest=Test.readfile(input);
			Arrays.sort(dest);
			PrintStreamoutput=newPrintStream(args[0]);
			Test.writefile(output,dest);
		}
		catch(FileNotFoundExceptione)
		{
			e.printStackTrace();
		}
	}
}

<Test3>
{
	inti;

	publicTest3(inti)
	{
		this.i=i;
	}

	@Override
	publicintcompareTo(Test3o)
	{
		if(o.i>i)
		{
			return-1;
		}
		elseif(o.i<i)
		{
			return1;
		}
		else
		{
			return0;
		}
	}

	@Override
	publicStringtoString()
	{
		returnString.format("%s",i);
	}

	publicstaticvoidmain(String[]args)
	{
		if(args.length!=3)
		{
			System.err.println("输入的参数个数不是3个");
			return;
		}
		LinkedList<Test3>list=newLinkedList<Test3>();
		try
		{
			Scannerinput1=newScanner(newFile(args[0]));
			Scannerinput2=newScanner(newFile(args[1]));
			while(true)
			{
				try
				{
					inta=Integer.parseInt(input1.nextLine().trim());
					intb=Integer.parseInt(input2.nextLine().trim());
					Test3ta=newTest3(a);
					Test3tb=newTest3(b);
					list.add(ta);
					list.add(tb);
				}
				catch(Exceptione)
				{
					break;
				}
			}
			input1.close();
			input2.close();
			Collections.sort(list);
			PrintStreamoutput=newPrintStream(args[2]);
			output.append(list.toString().replaceAll("[\[\]\s]","").replaceAll(",",Test.LINE));
			output.flush();
			output.close();
		}
		catch(FileNotFoundExceptione)
		{
			e.printStackTrace();
		}
	}
}

Ⅲ 用java io流把多个txt文件的内容合并到一个文件里

参考代悄春码如下：

public static void mergeFiles(String outFile, String[] files)

第一个参数是合并后生成文件的路早运枝径

第二个参数是你需要合并的文本文件列表

代码：

packageorg.lq.util;
importstaticjava.lang.System.out;

importjava.io.FileInputStream;
importjava.io.FileOutputStream;
importjava.io.IOException;
importjava.nio.ByteBuffer;
importjava.nio.CharBuffer;
importjava.nio.channels.FileChannel;
importjava.nio.charset.Charset;
importjava.nio.charset.CharsetDecoder;
importjava.nio.charset.CharsetEncoder;
importjava.util.Arrays;


publicclassMergeFile{
	publicstaticfinalintBUFSIZE=1024*8;
	publicstaticvoidmergeFiles(StringoutFile,String[]files){
		FileChanneloutChannel=null;
		out.println("Merge"+Arrays.toString(files)+"into"+outFile);
		try{
			outChannel=newFileOutputStream(outFile).getChannel();
			for(Stringf:files){
				Charsetcharset=Charset.forName("utf-8");
				CharsetDecoderchdecoder=charset.newDecoder();
				CharsetEncoderchencoder=charset.newEncoder();
				FileChannelfc=newFileInputStream(f).getChannel();
				ByteBufferbb=ByteBuffer.allocate(BUFSIZE);
				CharBuffercharBuffer=chdecoder.decode(bb);
				ByteBuffernbuBuffer=chencoder.encode(charBuffer);
				while(fc.read(nbuBuffer)!=-1){
					
					bb.flip();	
					nbuBuffer.flip();
					outChannel.write(nbuBuffer);
				bb.clear();
				nbuBuffer.clear();
				}
				fc.close();
			}
			out.println("Merged!!");
		}catch(IOExceptionioe){
			ioe.printStackTrace();
		}finally{
			try{if(outChannel!=null){outChannel.close();}}catch(IOException陆敏ignore){}
		}
	}
}

Ⅳ Java如何高效合并多个文件

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 test {
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("D:/output.txt", new String[]{"D:/in_1.txt", "D:/in_2.txt", "D:/in_3.txt"});
}
}