I am trying to use PrintWriter.java but I am getting a rather strange problem and I am not able to figure out what am I am missing here.
MyPrintWriter.java
public class MyPrintWriter {
public static void main(String[] args) {
File myFile = new File("myFileDirectory/myFileName.txt");
try {
FileWriter fw = new FileWriter(myFile);
PrintWriter pw = new PrintWriter(fw);
pw.println("Hello World!");
pw.close();
} catch (FileNotFoundException e) {
System.err.println("File not found: " + myFile);
} catch (Exception e) {
e.printStackTrace();
}
}
}
MyFileWriter.java
public class MyFileWriter {
public static void main(String[] args) {
File myFile = new File("myFileDirectory/myFileName.txt");
try {
InputStreamReader isr = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isr);
FileWriter fw = new FileWriter(myFile);
PrintWriter pw = new PrintWriter(fw);
String input;
input = br.readLine();
while(input != null) {
pw.println(input);
input = br.readLine();
}
br.close();
pw.close();
} catch (FileNotFoundException e) {
System.err.println("File not found: " + myFile);
} catch (Exception e) {
e.printStackTrace();
}
}
}
MyPrintWriter.java is happily writing to the myFileName.txt file but MyFileWrite.java can't.
Could someone help me understand what am I missing here?
You probably need to flush your print writer.
The PrintWriter constructor with a FileWriter parameter creates a PrintWriter with autoFlush set to off
Calling pw.flush() before pw.close(); should do the trick
来源：https://stackoverflow.com/questions/6734077/java-printwriter