Java学习之字节流-文件分割合并--2015-2-28

public class Test {

private static int size=1024;

public static void main(String[] args) throws Exception {
//切割的文件
File srcfile = new File("D:/workspace/Test/脸萌.JPG");
//切割文件的存放目录
File src = new File("");
//源文件目录
String descpath = "D:/workspace/parts";
//还原文件的存放路径
File desc = new File("D:/workspace");
//还原文件名称
String name = srcfile.getName();

//文件切割
splitFile(srcfile,descpath);
//文件合并
unionfile(desc,descpath,name);
}

public static void unionfile(File desc,String descpath,String name) throws Exception{
ArrayList<FileInputStream> list = new ArrayList<FileInputStream>();
File src = new File(descpath);
File[] files = src.listFiles(new FilenameFilter(){
@Override
public boolean accept(File dir, String name) {
return new File(dir,name).isFile() && name.endsWith(".part");
}
});

for(int i=1;i<=files.length;i++){
list.add(new FileInputStream(new File(src,i+".part")));
}
Enumeration<FileInputStream> en = Collections.enumeration(list);
SequenceInputStream sis = new SequenceInputStream(en);
FileOutputStream fos = new FileOutputStream(new File(desc,name));

byte[] by = new byte[1024];
int len=0;
while((len = sis.read(by))!=-1){
fos.write(by,0,len);
}
fos.flush();
fos.close();
sis.close();
}

//文件切割
public static void splitFile(File file,String descpath) throws Exception{
FileInputStream is = new FileInputStream(file);
FileOutputStream os = null;

File dir = new File(descpath);
if(!dir.isFile()){
dir.mkdirs();
}

byte[] car = new byte[size];
int len =0;
int count =1;
while((len=is.read(car))!=-1){
int num = count++;
os = new FileOutputStream(new File(dir,num+".part"));
os.write(car,0,len);
}
os.flush();
os.close();
is.close();
}
}