Java 输入和输出
解释以下用于将 int i 输出到文件的两个代码片段的输出之间的区别：
i)
PrintWriter outfile = new PrintWriter(new FileWriter("ints.txt"));
outfile.print(i);
ii)
DataOutputStream out = new DataOutputStream(new FileOutputStream("ints.dat"));
out.writeInt(i);
我认为打印机编写器采用字符串并将其转换为 unicode 字符流，而数据输出流则转换数据项目到字节序列。
您还想补充什么吗？
Explain the difference between the outputs of the following two fragments of code for outputting an int i to a file:
i)
PrintWriter outfile = new PrintWriter(new FileWriter("ints.txt"));
outfile.print(i);
ii)
DataOutputStream out = new DataOutputStream(new FileOutputStream("ints.dat"));
out.writeInt(i);
I think the Printer writer takes a string and tranforms it into a stream of unicode characters, whereas dataoutput stream converts the data items to sequence of bytes.
What more would you add?
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文件只包含字节，因此最终都以字节形式结束。
字符串已经是字符流。当您将字符串写入文件时，它必须将其转换为字节流。
一个 int 是四个字节。 writeInt() 将其转换为大端数。
Files only contain byte, so it all ends up as bytes in the end.
A String is already a stream of characters. When you write a String to a file it has to turn it into a stream of bytes.
An int is four bytes. writeInt() turns it into a big endian number.
来自
DataOutputStreamjavadoc：来自
PrintWriterjavadoc一切都只是字节，但它们代表不同的东西。使用
DataOutpuStream，您可以获得可以直接读回原始Java 类型int的字节，而使用PrintWriter则不行。From
DataOutputStreamjavadoc:From
PrintWriterjavadocEverything is just bytes, but they represent different things. With a
DataOutpuStreamyou get bytes that you can read back directly to your primitive Java typeint, whereas with aPrintWriteryou don't.可能会重复已经说过的内容，但只是为了使其更明确：
当您使用 printwriter 时，并说您的 int 值为 65 -
当您使用时 print writer 将打印 2 个字符：“6”和“5”一个输出流，它打印字节，因此它将向文件写入一个值为 65 的字节——这恰好是 ASCII/UTF-8 中“A”的字符代码，因此如果您在文本编辑器中打开该文件你会看到一个“A”字符——而不是上面的“6”后跟“5”。
possibly repeating what was already said, but just to make it more explicit:
when you use a printwriter, and say you have an int value of 65 -- the print writer will print 2 characters: '6' and '5'
when you use an outputstream, this prints bytes so it will write to the file a byte with the value of 65 -- this happens to be the character code in ASCII/UTF-8 for 'A' so if you open up the file in a text editor you will see an "A" character -- rather than '6' followed by '5' as above.