1、
import java.io.*;
//写进文档,然后又在显示器显示出来。
public class 
fileinputstream{
public static void main(String[] args) throws IOException 
{
DataOutputStream out = new DataOutputStream(new 
FileOutputStream("dest.txt"));
//定义要保存的数据数组。
double[] prices = { 19.99, 
9.99, 15.99 };
//将prices中的数据以Tab键为分割符保存在文件中。
for (int i = 0; i < 
prices.length; i ++) 
{
out.writeDouble(prices[i]);
out.writeChar(‘\t‘);
}
//*********Found********
out.close();
// 
创建数据输入流,将上面保存的文件再次打开并读取。
DataInputStream in = new DataInputStream(new 
FileInputStream("dest.txt"));
double price;
double total = 0.0;
for 
(int i = 0; i < prices.length; i ++) {
//*********Found********
price = 
in.readDouble();
in.readChar(); // 扔掉tab键
total = total + 
price;
}
System.out.println("For a TOTAL of: $" + 
total);
in.close();
}
}
2、
import java.io.File;
import java.io.FileInputStream;
import 
java.io.FileOutputStream;
import 
java.io.IOException;
//把source.txt文件的内容复制到dest.txt内容
public class fileinput2{
public static void main(String[] args) throws 
IOException{
File inputFile;
File outputFile;
FileInputStream 
in;
FileOutputStream out;
int c;
inputFile = new 
File("source.txt");
outputFile = new File("dest.txt");
in = new 
FileInputStream(inputFile);
//*********Found********
out=new 
FileOutputStream(outputFile);
while ((c = in.read()) != 
-1)
//*********Found********
out.write(c);
in.close();
out.close();
}
}
3、
import java.io.*;
public class fileinput3 {
public static void 
main(String[] args) {
char[] charArray = 
{‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘,‘g‘,‘h‘,‘i‘};
char c 
;
try{
//*********Found********** 文件流和数据输出流有什么区别
DataOutputStream out = 
new DataOutputStream(
new FileOutputStream("test.dat"));
for(int i =0; 
i<charArray.length; 
i++){
out.writeChar(charArray[i]);
}
//写进了文件,又读出来。
out.close();
DataInputStream 
in = new DataInputStream(
//*********Found**********
new 
FileInputStream("test.dat"));
while(in.available() != 
0){
c=in.readChar();
System.out.print(c+" 
");
}
System.out.println();
//*********Found**********
in.close();
}catch(IOException 
e){}
}
}
4、
import java.io.*;
public class fileinput4{
public static void 
main(String[] args){
int[] intArray = {1,2,3,4,5};
int j 
;
try{
DataOutputStream out = new DataOutputStream(
new 
FileOutputStream("data.dat"));
for(j =0; j<intArray.length; 
j++){
//*********Found********
out.writeInt(intArray[j]);
}
out.close();
DataInputStream in = new DataInputStream(
//*********Found********
new 
FileInputStream("data.dat"));
while(in.available() != 0)
{
j = 
in.readInt();
System.out.println(j);
}
in.close();
}
catch(IOException 
e){}
}
}
------------------------------------------------------
总结:一个是FileOutputStream 与FileInputStream
另外一个是DataOutputStream与DataInputStream
原文地址:http://www.cnblogs.com/bluewelkin/p/3715691.html