lru.java

操作系统课程设计：页面置换算法！！！很好的操作系统大作业

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package util;

import java.awt.Color;
import java.awt.Label;

/**
 *
 * @author Administrator
 */
public class LRU extends PageReplace{
    
    int[] seq=null;
    Label[] label=null;
    int []onLabel=null;
    int in;  //换进来页面
    int still;//原来就有又进来的
    int []come=null;
    double []efficiency=null; //换页率
    double formFeed=0;     //换页次数
    String nextSeq = null;
    String lastSeq = null;
    Label next = null;
    Label last = null;
    Label efficiencyLabel = null;
    
  public LRU(int[]s,double[] eff,Label[] l,Label next,Label last,Label efficiencyLabel)
  {
     seq=s;
      label=new Label[l.length];
      onLabel=new int[l.length];
      come = new int[l.length];
      efficiency= eff;
      this.next=next;
      this.last=last;
      this.efficiencyLabel = efficiencyLabel;
      for (int i = 0; i < l.length; i++) {
          label[i]= l[i];
          onLabel[i]=0;
          come[i]=0;
      }
      char[] show = new char[40];
      for (int i = 0,j=0; i < seq.length; i++) {
          show[j++] = (char)(seq[i]+48);
          show[j++] = ' ';
      }
      nextSeq = new String().valueOf(show);
      lastSeq = "";  
  }
  
    public void run()
  {
      next.setVisible(true);
      next.setText("待访问的页面编号为："+nextSeq);
      last.setVisible(true);
      last.setText("已访问的页面编号为："+lastSeq);      
      efficiencyLabel.setVisible(true);    
      
       int page=0;
      for (int i = 0; i < seq.length; i++) {
            try {
                in = -1;
                still = -1;
                if (page < label.length) {
                    for (int j = 0; j < page; j++) {
                        if (seq[i] == onLabel[j]) {
                            still = j;
                        }
                    }
                    if (still == -1) {
                        formFeed++;
                        in = page;
                        onLabel[page] = seq[i];
                        page++;
                    }
                    calCome(page);
                } else {
                    for (int j = 0; j < onLabel.length; j++) {
                        if (seq[i] == onLabel[j]) {
                            still = j;
                        }
                    }
                    if (still == -1) {
                        formFeed++;
                        in = 0;
                        for (int j = 1; j < label.length; j++) {
                            if (come[j] > come[in]) {
                                in = j;
                            }
                        }
                        onLabel[in] = seq[i];
                    }
                    calCome();
                }

                efficiency[i] = (double) (formFeed/(i+1));
                show(i);
                Thread.sleep(1000);
            } catch (Exception ex) {}
      }

  }
   
   private void calCome(int i)
   {
       for (int j = 0; j < i; j++) 
           come[j]++;
   }
   private  void calCome()
   {
        for (int j = 0; j < label.length; j++) 
           come[j]++;
        if(in!=-1)
            come[in]=0;
        else
            come[still]=0;
   }
   
   private void show(int cur) {
        for (int i = 0; i < label.length; i++) {
            label[i].setText(Integer.toString(onLabel[i]));
            label[i].setBackground(Color.CYAN);
        }
        if(still!=-1)
            label[still].setBackground(Color.green);
        else
            label[in].setBackground(Color.red);
        lastSeq = lastSeq.concat(nextSeq.substring(0, 2));
        nextSeq = nextSeq.substring(2);
        next.setText("待访问的页面编号为："+nextSeq);
        last.setText("已访问的页面编号为："+lastSeq);        
        efficiencyLabel.setText("当前缺页率为："+Double.toString(efficiency[cur]));
    }


}