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IO流(複製文字檔案的5種方式案例(用字元流)

package cn.itcast_01;

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

/*
 * 複製文字檔案
 * 
 * 分析:
 * 		複製資料,如果我們知道用記事本開啟並能夠讀懂,就用字元流,否則用位元組流。
 * 		通過該原理,我們知道我們應該採用字元流更方便一些。
 * 		而字元流有5種方式,所以做這個題目我們有5種方式。推薦掌握第5種。
 * 資料來源:
 * 		c:\\a.txt -- FileReader -- BufferdReader
 * 目的地:
 * 		d:\\b.txt -- FileWriter -- BufferedWriter
 */
public class CopyFileDemo {
	public static void main(String[] args) throws IOException {
		String srcString = "c:\\a.txt";
		String destString = "d:\\b.txt";
		// method1(srcString, destString);
		// method2(srcString, destString);
		// method3(srcString, destString);
		// method4(srcString, destString);
		method5(srcString, destString);
	}

	// 字元緩衝流一次讀寫一個字串
	private static void method5(String srcString, String destString)
			throws IOException {
		BufferedReader br = new BufferedReader(new FileReader(srcString));
		BufferedWriter bw = new BufferedWriter(new FileWriter(destString));

		String line = null;
		while ((line = br.readLine()) != null) {
			bw.write(line);
			bw.newLine();
			bw.flush();
		}

		bw.close();
		br.close();
	}

	// 字元緩衝流一次讀寫一個字元陣列
	private static void method4(String srcString, String destString)
			throws IOException {
		BufferedReader br = new BufferedReader(new FileReader(srcString));
		BufferedWriter bw = new BufferedWriter(new FileWriter(destString));

		char[] chs = new char[1024];
		int len = 0;
		while ((len = br.read(chs)) != -1) {
			bw.write(chs, 0, len);
		}

		bw.close();
		br.close();
	}

	// 字元緩衝流一次讀寫一個字元
	private static void method3(String srcString, String destString)
			throws IOException {
		BufferedReader br = new BufferedReader(new FileReader(srcString));
		BufferedWriter bw = new BufferedWriter(new FileWriter(destString));

		int ch = 0;
		while ((ch = br.read()) != -1) {
			bw.write(ch);
		}

		bw.close();
		br.close();
	}

	// 基本字元流一次讀寫一個字元陣列
	private static void method2(String srcString, String destString)
			throws IOException {
		FileReader fr = new FileReader(srcString);
		FileWriter fw = new FileWriter(destString);

		char[] chs = new char[1024];
		int len = 0;
		while ((len = fr.read(chs)) != -1) {
			fw.write(chs, 0, len);
		}

		fw.close();
		fr.close();
	}

	// 基本字元流一次讀寫一個字元
	private static void method1(String srcString, String destString)
			throws IOException {
		FileReader fr = new FileReader(srcString);
		FileWriter fw = new FileWriter(destString);

		int ch = 0;
		while ((ch = fr.read()) != -1) {
			fw.write(ch);
		}

		fw.close();
		fr.close();
	}
}