Sequence:可以将文件进行合并.
例如:
将 1.txt , 2.txt, 3.txt 合并为一个文件
我在1.txt , 2.txt, 3.txt 分别写的是 一行1 和 两行2 和 三行3
例子(一):
需要:将要合并的文件放入一个枚举类中
这时就需要Vector集合
Vector: 是同步的…线程安全…但是效率相对较低
import java.io.*;
import java.uilt.Vector;
public class Demo {
public static void main(String[] args) throws IOEception{
Vector<FileInputStream> v = new Vector<FileInputStream>();
v.add(new FileInputStream("1.txt"));
v.add(new FileInputStream("2.txt"));
v.add(new FileInputStream("3.txt"));
Enumeration en = v.elements();//返回枚举
SequenceInputStream sis = new SequenceInputStream (en);
//把合并的写入到123.txt;
FileOutputStream fos = new FileOutputStream("123.txt");
byte[] buf = new byte[1024];
int len = 0;
while((len = sis.read(buf)) != -1) {
fos.write(buf,0,len);
fos.flush();
}
sis.close();
fos.close();
}
}
运行结果:
![](https://img.laitimes.com/img/9ZDMuAjOiMmIsIjOiQnIsICM38FdsYkRGZkRG9lcvx2bjxiNx8VZ6l2cs0TPn10MrpnTwsmaNBDOsJGcohVYsR2MMBjVtJWd0ckW65UbM5WOHJWa5kHT20ESjBjUIF2X0hXZ0xCMx81dvRWYoNHLrdEZwZ1Rh5WNXp1bwNjW1ZUba9VZwlHdssmch1mclRXY39CXldWYtlWPzNXZj9mcw1ycz9WL49zZwpmL0UTOzUTN0AjM4EjMxkTMwIzLc52YucWbp5GZzNmLn9Gbi1yZtl2Lc9CX6MHc0RHaiojIsJye.jpg)
例子(二):
因为我们使用Vector效率比较低, 所有我们使用ArrayList这个集合
因为ArrayList没有枚举方法…
所有使用Collections这个静态集合工具类
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
public class Demo {
public static void main(String[] args) throws IOException {
ArrayList<FileInputStream> al = new ArrayList<FileInputStream>();
al.add(new FileInputStream("1.txt"));
al.add(new FileInputStream("2.txt"));
al.add(new FileInputStream("3.txt"));
Enumeration<FileInputStream> en = Collections.enumeration(al);
SequenceInputStream sis = new SequenceInputStream(en);
FileOutputStream fos = new FileOutputStream("123.txt");
byte[] buf = new byte[1024];
int len = 0;
while((len = sis.read(buf)) != -1) {
fos.write(buf,0,len);
}
fos.close();;
}
}
运行结果:
与例子(一)相同