IO流-文件拷贝

其实文件的拷贝还是文件读取写入的应用，实际是读取此路径上的文件，然后写入到指定路径下的文件。

代码举例：

import java.io.*;
import java.lang.*;
class Test
{
    public static void main(String[] args)
    {
        copy("C:\\log.txt", "d:\\log.txt");
    }
    //块读取方式
    public static void copy(String sourcePath, String destPath)
    {
        final int READCACHELEN = 1024;
        try(FileReader fileReader = new FileReader(sourcePath))
        {
            int readReturnNum = 0;
            char[] readCache = new char[READCACHELEN];
            try(FileWriter fileWriter = new FileWriter(destPath, true))//定义添加为真
            {
                while((readReturnNum = fileReader.read(readCache)) != -1)
                {
                    fileWriter.write(readCache, 0, readReturnNum);
                }
            }
            catch(Exception e)
            {
                e.printStackTrace();
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        
       System.out.println("transport Ok!");
    }
    //单个字符读取方式
    public static void copy(String sourcePath, String destPath)
    {
        final int READCACHELEN = 1024;
        try(FileReader fileReader = new FileReader(sourcePath))
        {
            int readReturnNum = 0;
            try(FileWriter fileWriter = new FileWriter(destPath, true))
            {
                while((readReturnNum = fileReader.read()) != -1)//read读取单个字符以整型返回
                {
                    fileWriter.write(readReturnNum);
                }
            }
            catch(Exception e)
            {
                e.printStackTrace();
            }
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        
       System.out.println("transport Ok!");
    }
}