#vulnerable code 
                                public static String readInFile(File file) {
        try {
            FileChannel fc = new FileInputStream(file).getChannel();
            ByteBuffer buf = allocateDirect(10);
            StringAppender appender = new StringAppender();
            int read;

            while (true) {
                buf.rewind();
                if ((read = fc.read(buf)) != -1) {
                    buf.rewind();
                    for (; read != 0; read--) {
                        appender.append((char) buf.get());
                    }
                }
                else {
                    break;
                }
            }

            return appender.toString();
        }
        catch (FileNotFoundException e) {
            throw new TemplateError("cannot include template '" + file.getName() + "': file not found.");
        }
        catch (IOException e) {
            throw new TemplateError("unknown I/O exception while including '" + file.getName() + "' (stacktrace nested)", e);
        }
    } 
                            #location 21 
                            #vulnerability type RESOURCE_LEAK
#fixed code
                                public static String readInFile(File file) {
        try {
            FileChannel fc = new FileInputStream(file).getChannel();
            ByteBuffer buf = allocateDirect(10);
            StringAppender appender = new StringAppender();
            int read;

            while (true) {
                buf.rewind();
                if ((read = fc.read(buf)) != -1) {
                    buf.rewind();
                    for (; read != 0; read--) {
                        appender.append((char) buf.get());
                    }
                }
                else {
                    break;
                }
            }

            fc.close();

            return appender.toString();
        }
        catch (FileNotFoundException e) {
            throw new TemplateError("cannot include template '" + file.getName() + "': file not found.");
        }
        catch (IOException e) {
            throw new TemplateError("unknown I/O exception while including '" + file.getName() + "' (stacktrace nested)", e);
        }
    }