import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.nio.channels.FileChannel;
import java.nio.ByteBuffer;

public class Test{
public static void main(String[] args) throws Exception {
????? //創建2個文件
?? File file1 = new File("D://test1.txt");
?? File file2 = new File("d://test2.txt");
?? file1.createNewFile();
?? file2.createNewFile();
??
?? //從鍵盤輸入的字符寫入test1.txt
?? FileWriter fout = new FileWriter(file1);
?? String str=null;
?? System.out.println("Please input a String:");
?? BufferedReader fin = new BufferedReader(new InputStreamReader(System.in));
?? str = fin.readLine();
?? System.out.println(str);
?? fout.write(str,0,str.length());
?? fout.flush();
?? fout.close();
?? fin.close();
??
?? //復制文件test1.txt的內容到test2.txt
?? //為了讓你明白通道所以我這里用了2種讀寫入文件的方法
?? new Exam2().copy("D://test1.txt", "d://test2.txt");
??
}
/**
? * 復制文件封裝類
? * @param url1
? * @param url2
? * @throws Exception
? */
public void copy(String url1, String url2) throws Exception {
? FileInputStream input = new FileInputStream(url1);
? FileChannel filechannel = input.getChannel();
? FileOutputStream output = new FileOutputStream(url2);
? FileChannel filechannel2 = output.getChannel();
? ByteBuffer buf = ByteBuffer.allocate(1024 * ;
? while (filechannel.read(buf) != -1) {
?? buf.flip();
?? filechannel2.write(buf);
?? buf.clear();
? }
? input.close();
? filechannel.close();
? output.close();
? filechannel2.close();
}
}

java寫入