I am simply trying to write my 2d array "puzzle" to a file. I have a double for loop which reads through each of the 'char' values in my array and supposedly writes them to the file. I can't seem to find the error in my code. The file says it is modified when I run the program, but it is still blank. Thanks guys!
public void writeToFile(String fileName)
{
try{
PrintWriter pW = new PrintWriter(new File(fileName));
for(int x = 0; x < 25; x++)
{
for(int y = 0; y < 25; y++)
{
pW.write(puzzle[x][y]);
}
pW.println();
}
}
catch(IOException e)
{
System.err.println("error is: "+e.getMessage());
}
}
解決方案
Close your PrintWriter in a finally block to flush it and to reclaim resources
public void writeToFile(String fileName) {
// **** Note that pW must be declared before the try block
PrintWriter pW = null;
try {
pW = new PrintWriter(new File(fileName));
for (int x = 0; x < 25; x++) {
for (int y = 0; y < 25; y++) {
pW.write(puzzle[x][y]);
}
pW.println();
}
} catch (IOException e) {
// System.err.println("error is: "+e.getMessage());
e.printStackTrace(); // *** this is more informative ***
} finally {
if (pW != null) {
pW.close(); // **** closing it flushes it and reclaims resources ****
}
}
}
Caveat: Code not tested nor compiled.
Note that another option is to use try with resources.