我只是回顾一下我们在一个java类中编写的代码,我注意到在finally块中有一个关闭阅读器的try/catch,但不是作者。我会复制下面的代码。任何人都可以解释为什么会这样吗?我想更好地理解。关闭阅读器和写入器的异常处理
public class UsingFiles {
public static void main(String[] args) {
// open the input stream (from the file of this program)
BufferedReader reader = null;
PrintWriter writer = null;
try {
reader = new BufferedReader(new FileReader("./src/UsingFiles.java"));
writer = new PrintWriter("reverseFile.txt");
// String line;
// while ((line = reader.readLine()) != null) {
// System.out.println(line);
// }
// print the file in reverse order
// use recursion
reverseFile(reader, writer);
} catch (FileNotFoundException e) {
System.out.println("Couldn't open the file!");
} catch (IOException e) {
System.out.println("Problem reading the file");
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
System.out.println("Couldn't close the reader");
}
}
if (writer != null) {
writer.close();
}
}
}
private static void reverseFile(BufferedReader reader, PrintWriter writer)
throws IOException {
String line = reader.readLine();
if (line != null) {
reverseFile(reader, writer);
writer.println(line);
}
}