| dReader：与BufferedInputStream对应
3) LineNumberReader：与LineNumberInputStream对应
4) PushBackReader：与PushbackInputStream对应
FilterOutStream的各种类型
用于封装以字节为导向的OutputStream
1) DataIOutStream：往stream中输出基本类型（int、char等）数据。
2) BufferedOutStream：使用缓冲区
3) PrintStream：产生格式化输出
用于封装以字符为导向的OutputStream
1) BufferedWrite：与对应
2) PrintWrite：与对应
三.RandomAccessFile
1.可通过RandomAccessFile对象完成对文件的读写操作
2.在产生一个对象时，可指明要打开的文件的性质：r，只读；w，只写；rw可读写
3.可以直接跳到文件中指定的位置
详解Java编程中的IO系统(3)
时间:2010-04-27
四.I/O应用的一个例子
import java.io.*;
public class TestIO{
public static void main(String[] args)
throws IOException{
//1.以行为单位从一个文件读取数据
BufferedReader in =
new BufferedReader(
new FileReader("F:\nepalon\TestIO.java"));
String s, s2 = new String();
while((s = in.readLine()) != null)
s2 += s + "
";
in.close();
//1b.接收键盘的输入
BufferedReader stdin =
new BufferedReader(
new InputStreamReader(System.in));
System.out.println("Enter a line:");
System.out.println(stdin.readLine());
//2.从一个String对象中读取数据
StringReader in2 = new StringReader(s2);
int c;
while((c = in2.read()) != -1)
System.out.println((char)c);
in2.close();
//3.从内存取出格式化输入
try{
DataInputStream in3 =
new DataInputStream(
new ByteArrayInputStream(s2.getBytes()));
while(true)
System.out.println((char)in3.readByte());
}
catch(EOFException e){
System.out.println("End of stream");
}
//4.输出到文件
try{
BufferedReader in4 =
new BufferedReader(
new StringReader(s2));
PrintWriter out1 =
new PrintWriter(
new BufferedWriter(
new FileWriter("F:\nepalon\ TestIO.out")));
int lineCount = 1;
while((s = in4.readLine()) != null)
out1.println(lineCount++ + "：" + s);
out1.close();
in4.close();
}
catch(EOFException ex){
System.out.println("End of stream");
}
//5.数据的存储和恢复
try{
DataOutputStream out2 =
new DataOutputStream(
new BufferedOutputStream(
new FileOutputStream("F:\nepalon\ Data.txt")));
out2.writeDouble(3.1415926);
out2.writeChars("
Thas was pi:writeChars
");
out2.writeBytes("Thas was pi:writeByte
");
out2.close();
DataInputStream in5 =
new DataInputStream(
new BufferedInputStream(
new FileInputStream("F:\nepalon\ Data.txt")));
BufferedReader in5br =
new BufferedReader(
new InputStreamReader(in5));
System.out.println(in5.readDouble());
System.out.println(in5br.readLine());
System.out.println(in5br.readLine());
}
catch(EOFException e){
System.out.println("End of stream");
}
//6.通过RandomAccessFile操作文件
RandomAccessFile rf =
new RandomAccessFile("F:\nepalon\ rtest.dat", "rw");
for(int i=0; i<10>
rf.writeDouble(i*1.414);
rf.close();
rf = new RandomAccessFile("F:\nepalon\ rtest.dat", "r");
for(int i=0; i<10>
System.out.println("Value " + i + "：" + rf.
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