【IO流】读写文件的五种方式

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package com.it;

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

public class FileReaderAndFileWriter {
	public static void main(String[] args) throws IOException {
		method01();
	}

	public static void method01() {
		FileReader fr = new FileReader("BufferedReaderDemo.java");
		FileWriter fw = new FileWriter("copy1.txt");
		int ch;
		while (-1 != (ch = fr.read())) {
			System.out.print((char)ch);
			fw.write((char)ch);
			fw.flush();
		}
		fw.close();
		fr.close();
	}

	public static void method02() {
		FileReader fr = new FileReader("BufferedReaderDemo.java");
		FileWriter fw = new FileWriter("copy2.txt");
		int len;
		char[] ch = new char[1024];
		while (-1 != (len = fr.read(ch))) {
			System.out.println(new String(ch, 0, len));
			fw.write(new String(ch, 0, len));
			fw.flush();
		}
		fw.close();
		fr.close();
	}
}

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package com.it;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class BufferedReaderAndBufferedWriterDemo {
	public static void main(String[] args) throws IOException {
		method03();
	}

	public static void method03() {
		BufferedReader br = new BufferedReader(new FileReader("BufferedReaderDemo.java"));
		BufferedWriter bw = new BufferedWriter(new FileWriter("copy3.txt"));
		int ch;
		while (-1 != (ch = br.read())) {
			System.out.print((char)ch);
			bw.write((char)ch);
			bw.flush();
		}
		bw.close();
		br.close();
	}

	public static void method04() {
		BufferedReader br = new BufferedReader(new FileReader("BufferedReaderDemo.java"));
		BufferedWriter bw = new BufferedWriter(new FileWriter("copy4.txt"));
		int len;
		char[] ch = new char[1024];
		while (-1 != (len = br.read(ch))) {
			System.out.print(new String(ch, 0, len));
			bw.write(ch, 0, len);
			bw.flush();
		}
		bw.close();
		br.close();
	}

	public static void method05() {
		BufferedReader br = new BufferedReader(new FileReader("BufferedReaderDemo.java"));
		BufferedWriter bw = new BufferedWriter(new FileWriter("copy5.txt"));
		String line;
		while (null != (line = br.readLine())) {
			System.out.println(line);
			bw.write(line);
			//bw.write("rn");
			bw.newLine();
			bw.flush();
		}
		bw.close();
		br.close();
	}
}