JAVA学习第五十五课 — IO流（九）文件切割合成器

文件切割器

private static final int SIZE = 1024 *1024;public static void splitFile(File file) throws IOException{//用读取流关联文件（不确定文件格式）FileInputStream fis = new FileInputStream(file);//源是一个byte[] by = new byte[SIZE];//定义1M的缓冲区FileOutputStream fos = null;//汇不知道有多少个int len = 0;int count = 1;//记录子文件个数File dir = new File("D:\\patFiles");if(!dir.isFile()){dir.mkdirs();}while((len = fis.read(by))!=-1){fos = new FileOutputStream(new File(dir,(count++)+".part"));//自定义文件格式fos.write(by,0,len);}fos.close();fis.close();}

文件合并

public static void main(String[] args) throws IOException {File file = new File("D:\\PartFile");Merge(file);}public static void Merge(File dir)throws IOException{ArrayList<FileInputStream> AL = new ArrayList<FileInputStream>();for(int i = 1;i<=7;i++){AL.add(new FileInputStream(new File(dir,i+".part")));}Enumeration<FileInputStream> en = Collections.enumeration(AL);SequenceInputStream sis = new SequenceInputStream(en);FileOutputStream fos = new FileOutputStream(new File(dir,"盛夏光年.mp3"));byte[] by = new byte[1024];int len = 0;while((len = sis.read(by))!=-1){fos.write(by, 0, len);}sis.close();fos.close();}

文件切割合并+配置文件

import java.io.*;import java.util.ArrayList;import java.util.Collections;import java.util.Enumeration;import java.util.Properties;public class Main {private static final int SIZE = 1024 *1024;public static void main(String[] args) throws IOException {File file1 = new File("d:\\NeedSplit\\盛夏光年.mp3");File file2 = new File("D:\\PartFiles");splitFile(file1);Merge_1(file2);}public static void splitFile(File file) throws IOException{//用读取流关联文件（不确定文件格式）FileInputStream fis = new FileInputStream(file);//源是一个byte[] by = new byte[SIZE];//定义1M的缓冲区FileOutputStream fos = null;//汇不知道有多少个int len = 0;int count = 1;//记录子文件个数/*切割文件必须要记录切割文件的名称和切割处理的碎片文件的个数，方便合并 * 这个信息为了进行描述，使用键值对的方法，所以使用Properties对象*/Properties pro = new Properties();File dir = new File("D:\\PartFiles");if(!dir.isFile()){dir.mkdirs();}while((len = fis.read(by))!=-1){fos = new FileOutputStream(new File(dir,(count++)+".part"));//自定义文件格式fos.write(by,0,len);fos.close();}//将切割后文件的信息保存在pro集合中pro.setProperty("partCount", count+"");pro.setProperty("fileName", file.getName());fos = new FileOutputStream(new File(dir,count+".properties"));//将pro集合的信息存储在集合中pro.store(fos, "save file infmation");fis.close();}public static void Merge_1(File dir)throws IOException{//获取指定目录下配置文件对象File[] files = dir.listFiles(new SuffixFilter(".properties"));//new一个过滤器if(files.length!=1){throw new RuntimeException(dir+"该目录下没有properties扩展名的文件或者不唯一 ");}//记录配置文件对象File confile = files[0];//获取配置文件信息Properties pro = new Properties();FileInputStream fis = new FileInputStream(confile);//关联流对象pro.load(fis);//加载信息String filename  = pro.getProperty("fileName");//得到文件名int count = Integer.parseInt(pro.getProperty("partCount"));//得到碎片个数//获取该目录下的所有碎片文件//定义过滤器，判断碎片文件的个数与配置信息中的碎片信息是否一致File[] partFiles = dir.listFiles(new SuffixFilter(".part"));if(partFiles.length!=(count-1)){throw new RuntimeException("碎片文件个数不对，应是"+count+"个！");}//将碎片文件和流对象关联，并存储集合中ArrayList<FileInputStream> AL = new ArrayList<FileInputStream>();for(int i = 0;i<partFiles.length;i++){AL.add(new FileInputStream(partFiles[i]));}//将多个流合并成一个序列流Enumeration<FileInputStream> en = Collections.enumeration(AL);SequenceInputStream sis = new SequenceInputStream(en);//读写过程FileOutputStream fos = new FileOutputStream(new File(dir,filename));byte[] by = new byte[1024];int len = 0;while((len = sis.read(by))!=-1){fos.write(by, 0, len);}sis.close();fos.close();}}