操作系統(tǒng)實(shí)習(xí)報(bào)告 -1

操作系統(tǒng)實(shí)習(xí)報(bào)告日期：實(shí)習(xí)題目：基于Windows環(huán)境的讀者寫者問題完成人姓名：楊雪亞班級：物聯(lián)網(wǎng)工程學(xué)號：2014141461034實(shí)習(xí)內(nèi)容簡要描述創(chuàng)建一個(gè)控制臺進(jìn)程。此進(jìn)程包含n個(gè)線程。用這n個(gè)線程來表示n個(gè)讀者或?qū)懻?。每個(gè)線程按相應(yīng)測試數(shù)據(jù)文件(后面有介紹)的要求進(jìn)行讀寫操作。用信號量機(jī)制分別實(shí)現(xiàn)讀者優(yōu)先和寫者優(yōu)先的讀者-寫者問題。運(yùn)行結(jié)果顯示要求：要求在每個(gè)線程創(chuàng)建、發(fā)出讀寫操作申請、開始讀寫操作和結(jié)束讀寫操作時(shí)分別顯示一行提示信息，以確定所有處理都遵守相應(yīng)的讀寫操作限制。主要代碼結(jié)構(gòu)（附注釋）publicclassreaderfirst{classwriterextendsThread{//寫者進(jìn)程publicwriter(intno,doublest,doublert);publicvoidrun();}classreaderextendsThread{//讀者進(jìn)程publicreader(intno,doublest,doublert);publicvoidrun();}publicvoidrun();//數(shù)據(jù)寫入和讀取publicstaticvoidmain(Stringargs[]){//主程序 (newreaderfirst()).run(); }}結(jié)果分析（或錯(cuò)誤原因分析）運(yùn)行結(jié)果如左注釋：如果上述表格空間不夠，可以另附表格進(jìn)行說明附代碼:importjava.util.concurrent.Semaphore;publicclassreaderfirst{ Semaphoremutex=newSemaphore(1);//提供互斥reader_count信號量 Semaphorewrt=newSemaphore(1);//提供讀者寫者同步信號量 intrwn=0;//讀者等待數(shù) intreader_count=0;//讀者數(shù)，初始值為0 classwriterextendsThread{//寫者進(jìn)程 intnum; doublesleeptime; doubleruntime; publicwriter(intno,doublest,doublert){ num=no; sleeptime=st; runtime=rt; } publicvoidrun(){ try{ sleep((int)(sleeptime*1000)); System.out.println("第"+num+"號寫者想寫,現(xiàn)在共有讀者"+reader_count +"個(gè)"); if(rwn==0){ wrt.acquire(); System.out.println("第"+num+"號寫者正在寫，請等待..."); sleep((int)(runtime*1000)); System.out.println("第"+num+"號寫者寫完了"); wrt.release(); } }catch(InterruptedExceptione){ //TODOAuto-generatedcatchblock e.printStackTrace(); }System.out.println(num+”“+sleeptime+”“+runtime); } } classreaderextendsThread{//讀者進(jìn)程 intnum; doublesleeptime; doubleruntime; publicreader(intno,doublest,doublert){ num=no; sleeptime=st; runtime=rt; } publicvoidrun(){ try{ sleep((int)(sleeptime*1000)); System.out.println("第"+num+"號讀者想讀"); rwn++; mutex.acquire(); rwn--; if(reader_count==0){ wrt.acquire(); } reader_count++; System.out.println("第"+num+"號讀者正在讀"); System.out.println("現(xiàn)在共有"+reader_count+"個(gè)讀者"); mutex.release(); sleep((int)(runtime*1000)); mutex.acquire(); reader_count--; System.out.println("第"+num+"號讀者讀完了,此時(shí)共有"+reader_count +"個(gè)讀者"); if(reader_count==0){ wrt.release(); } mutex.release(); }catch(InterruptedExceptione){ //TODOAuto-generatedcatchblock e.printStackTrace(); }System.out.println(num+”“+sleeptime+”“+runtime); } } publicvoidrun(){ readerr1=newreader(1,3,5); writerw2=newwriter(2,4,5); readerr3=newreader(3,5,2); readerr4=newreader(4,6,5); writerw5=newwriter(5,5.2,3);