java编程输入输出问题

[a782434501]

java中FileWriter类对象如何向文件中写入长整型？我是初学者，希望有大侠帮我解答下呀

[huntor]

PrintWriter writer = new PrintWriter(new FileWriter(...));
writer.println(1123L);
writer.print(13232L);

[a782434501]

楼上的高手！我的题目只让用Filewriter呀，还有别的办法没呀

[BearKin]

[Quote=引用楼主 a782434501 的回复:]
java中FileWriter类对象如何向文件中写入长整型？我是初学者，希望有大侠帮我解答下呀
[/Quote]

FileWriter写入长整型是什么意思? 不让用DataOutputStream么... 稍后代码奉上

[BearKin]

package util;

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class FileWriterTester {
	public static void main(String[] args) throws IOException {
		long l = 4657646574646L;
		FileWriter writer = new FileWriter("D:/temp");
		writer.write(longToChar(l));
		writer.flush();
		writer.close();
		FileReader reader = new FileReader("D:/temp");
		char[] c = new char[4];
		reader.read(c);
		reader.close();
		System.err.println(charToLong(c) == l);
		new File("D:/temp").delete();
	}

	public static char[] longToChar(long l) {
		char[] chars = new char[4];
		for (int i = 0; i < 4; i++) {
			chars[i] = (char) (l << (i * 16) >> (16 * 3));
		}
		return chars;
	}

	public static long charToLong(char[] c) {
		long result = 0;
		for (int i = 0; i < 4; i++) {
			long temp = c[i];
			result |= temp << (16 * (3 - i));
		}
		return result;
	}
}

搞定..

[huntor]

writer 支持写字符串，

write(Long.toString(234343434L));

[happysmhzp]

应该没有了吧