ioproblem.java

来自「thinking in Java书中 的源代码」· Java 代码 · 共 38 行

//: c11:IOProblem.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// Java 1.1 and higher I/O Problem.
import java.io.*;

public class IOProblem {
  // Throw exceptions to console:
  public static void main(String[] args) 
  throws IOException {
    DataOutputStream out =
      new DataOutputStream(
        new BufferedOutputStream(
          new FileOutputStream("Data.txt")));
    out.writeDouble(3.14159);
    out.writeBytes("That was the value of pi\n");
    out.writeBytes("This is pi/2:\n");
    out.writeDouble(3.14159/2);
    out.close();

    DataInputStream in =
      new DataInputStream(
        new BufferedInputStream(
          new FileInputStream("Data.txt")));
    BufferedReader inbr =
      new BufferedReader(
        new InputStreamReader(in));
    // The doubles written BEFORE the line of text
    // read back correctly:
    System.out.println(in.readDouble());
    // Read the lines of text:
    System.out.println(inbr.readLine());
    System.out.println(inbr.readLine());
    // Trying to read the doubles after the line
    // produces an end-of-file exception:
    System.out.println(in.readDouble());
  }
} ///:~