Java fileReader无法正确读取文件

Question

我正在创建一个类，它读取一个数字文件，并将它们返回到我的程序中。然而，当我在文件中读取时，即使有一个文件存在并包含内容，文件也会返回null。代码如下：

try {
File help = new File("colours.txt");
help.createNewFile();

FileWriter myWriter = new FileWriter(help);
myWriter.write("1 2 3 4 5 6 7");

BufferedReader reader = new BufferedReader(new FileReader(help));
String line = reader.readLine();
while(line != null) {
System.out.println(line);
line = reader.readLine();
}
reader.close();
myWriter.close();
}catch(IOException e) {
System.out.println("There was an error");
}

Answer 1

关闭文件，以便在读取之前将内容写入硬盘。

try {
File help = new File("colours.txt");
help.createNewFile();

FileWriter myWriter = new FileWriter(help);
myWriter.write("1 2 3 4 5 6 7");
myWriter.close();
//Close the file before reading it.
//Your changes will be added to the file

BufferedReader reader = new BufferedReader(new FileReader(help));
String line = reader.readLine();

while(line != null) {
System.out.println(line);
line = reader.readLine();
}

reader.close();
myWriter.close();

}catch(IOException e) {
System.out.println("There was an error");
}