JAVA程序中怎么把信息存到文件中

这个问题就是涉及到标准输入输出IO的问题啊。我给你写一个程序你想看看！
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 {
//创建2个文件
File file1 = new File("D://test1.txt");
File file2 = new File("d://test2.txt");
file1.createNewFile();
file2.createNewFile();

//从键盘输入的字符写入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.flus