testreplacement.java

lru页面置换算法 随机序列 java源代码

import java.util.*;
public class TestReplacement 
{
private final int ArraySize=20;
private int digitalArray[]=new int [ArraySize];

//private int digitalArray[]={1,2,3,4,2,1,5,6,2,1,2,3,7,6,3,2,1,2,3,6};

private static final int frameSize[]={1,2,3,4,5,6,7};
private static int errorCount=0; 

Vector frame=new Vector();
    
public TestReplacement() {
  super();
  // TODO Auto-generated constructor stub
}

public static void main(String[] args) {
  TestReplacement aT=new TestReplacement();
  
  aT.generateRandomDigit();
  aT.output();
  
  System.out.println("-------------Using FIFO--------------");
  System.out.println();
  for(int i=0;i<frameSize.length;i++){
  System.out.println("Frame size:  "+frameSize+"\n");
  aT.initFrameForFIFO(frameSize);
  aT.FIFOReplace(frameSize); 
  System.out.println("Total errors found:  "+errorCount);  
  System.out.println("\n************************************\n");
  
  errorCount=0;
  }
  System.out.println();
  System.out.println("----------------Using LRU----------------");
  System.out.println();
  for(int i=0;i<frameSize.length;i++){
  System.out.println("Frame size:  "+frameSize+"\n");
  aT.initFrameForLRU(frameSize);
  aT.LRUReplace(frameSize); 
  System.out.println("Total errors found:  "+errorCount);
  System.out.println("\n************************************\n");
  errorCount=0;
  }
}

public void generateRandomDigit(){
  for(int i=0;i<ArraySize;i++){
  digitalArray=(int)Math.round(Math.random()*9);
  }
}

public void output(){
  System.out.println("随机序列：");
  for(int i=0;i<ArraySize;i++){
  System.out.print(" "+digitalArray);
  }
  System.out.println();
}

public void initFrameForFIFO(int fS){
  frame.removeAllElements();
  for(int i=0;i<fS;i++){  
  frame.addElement(new Couple(fS-i));
  } 
}
public void initFrameForLRU(int fS){
  frame.removeAllElements();
  for(int i=0;i<fS;i++){  
  frame.addElement(new Couple(0));
  } 
}


public void LRUReplace(int fS){
        boolean findThesame=false;
        int pre=-1;//存放刚刚查找到的位置
        int flag=-1;
        
  for(int j=0;j<digitalArray.length;j++){
  boolean match=false;
  for(int i=0;i<fS;i++){  
    
    if(((Couple)frame.elementAt(i)).value==digitalArray[j]){
    ((Couple)frame.elementAt(i)).time=0;
    match=true;//是否找到匹配 
    System.out.println(j+": find "+((Couple)frame.elementAt(i)).value+" "+"at location "+i);
    System.out.println();    
    
    flag=i;
    break;    
    }
  }
  
  if(match==true&&flag!=pre){
    for(int i=0;i<fS;i++){
    if(i!=flag){
    ((Couple)frame.elementAt(i)).time--;
    }      
    }
    pre=flag;
  }
  else if(match==false){
    int temp=0;
    int index=0;
    for(int i=0;i<fS;i++){
    if(((Couple)frame.elementAt(i)).time<temp){
      temp=((Couple)frame.elementAt(i)).time;
      index=i;
    } 
    } 
    for(int i=0;i<fS;i++){
    if(i!=index){
      ((Couple)frame.elementAt(i)).time--;
    }
    else{
      ((Couple)frame.elementAt(i)).time=0;
      System.out.print(j+": replace "+((Couple)frame.elementAt(i)).value+" ");      
      System.out.print("at location "+index+" ");
      ((Couple)frame.elementAt(i)).value=digitalArray[j];
      System.out.println("with "+((Couple)frame.elementAt(i)).value);
      errorCount++;
      System.out.println("error count    "+errorCount);
      System.out.println();
    }
    }
  }
  }  
}
public void FIFOReplace(int fS){
  //boolean blank=true;//是否开始的已填充完
  int i=0;
  for(int j=0;j<digitalArray.length;j++){  
  boolean match=false;
  for(i=0;i<fS;i++){
    if(((Couple)frame.elementAt(i)).value==digitalArray[j]){
    match=true;//是否找到匹配
    System.out.println(j+": find "+((Couple)frame.elementAt(i)).value+" "+"at location "+i);
    break;
    }
  }
  if(match==false){
    int temp=0;
    int index=-1;
    for(i=0;i<fS;i++){    
    if(((Couple)frame.elementAt(i)).time>temp){
      temp=((Couple)frame.elementAt(i)).time;
      index=i;
    }
    }
    for(i=0;i<fS;i++){
        if(i==index){
      System.out.print(j+": replace "+((Couple)frame.elementAt(i)).value+" ");      
      System.out.print("at location "+i+" ");
          ((Couple)frame.elementAt(i)).value=digitalArray[j];
          System.out.println("with "+((Couple)frame.elementAt(i)).value);
      ((Couple)frame.elementAt(i)).time=1;
        errorCount++; 
        System.out.println("error count    "+errorCount);
        System.out.println();
      }
      
      
      
      else{
      ((Couple)frame.elementAt(i)).time++;
      }
    
    
    
    }
  }