对不起,我是菜鸟中的菜鸟.请问JDK在哪里下,还有跟JDSK有什么区别
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import java.io.*; public class ExReandom0{ public static void main(String[] args) throws IOException, InterruptedException { int i=0;int j=0; RandomAccessFile str=new RandomAccessFile("c:/aa.txt", "rw");//str是文件源头对象 RandomAccessFile putOut=new RandomAccessFile("c:/java/haha.txt","rw");//putOot文件目的对象 i=(int) str.length(); j=(int) putOut.length(); System.out.println("文件总长度:"+i); System.out.println("已下载:"+j); if(i>j){ System.out.println("正在下载...请等待....."); str.seek(j); putOut.seek(j); Thread.sleep(3000); putOut.writeBytes(str.readLine()); } System.out.println("下载完毕"); putOut.close(); str.close(); }
} //这个是分行下载程序的基本原理