simulador_cache_com_redundacia/src/cache/LRU.java

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package cache;

/**
 *
 * @author Juninho Carlos
 */
public class LRU {    
    private int[] traceLRU;
    
    public LRU(){
        this.traceLRU = new int[4]; 
        for(int i = 0; i < 4; i++){
            this.traceLRU[i] = -1;
        }
    }
    
    public int[] getTraceLRU(){
        return this.traceLRU;
    }
    
    private boolean isCheio(){
        for(int i = 0; i < 4; i++){            
            if(this.traceLRU[i]==-1){
                return false;
            }
        }
        return true;
    }
    
    private int getIndexFromBloco(int num_bloco){
        for(int i = 0; i < 4; i++){
            if(this.traceLRU[i] == num_bloco){
                return i;
            }            
        }
        return -1;
    }
    
    private boolean containsBloco(int num_bloco){
        for(int i = 0; i < 4; i++){
            if(this.traceLRU[i] == num_bloco){
                return true;
            }
        }
        return false;
    }
    
    private void atualizaTraceLRU(int indexDoAcesso){
        int bloco = this.traceLRU[indexDoAcesso];
        
        for(; indexDoAcesso < 3 && this.traceLRU[indexDoAcesso] != -1 ;indexDoAcesso++){
            this.traceLRU[indexDoAcesso] = this.traceLRU[indexDoAcesso+1];
        }        
        this.traceLRU[indexDoAcesso-1] = bloco;
    }
    
    private void insereNoFinal(int numBloco){
        for(int i =0; i<4; i++){
            if(this.traceLRU[i] == -1){
                this.traceLRU[i] = numBloco;
                return;
            }
        }
    }
    
    public void atualizaLRU(int bloco){        
        //Caso o trace ainda não tenha sido preenchido
        
        
        if(!isCheio() && containsBloco(bloco)){
            
            this.atualizaTraceLRU(getIndexFromBloco(bloco));
            return;
        }else if(!isCheio()){
            
            this.insereNoFinal(bloco);
            return;
        }
        
        
        //Caso já tenha sido preenchido
        int indiceBloco = 0;
        for(; indiceBloco < 4; indiceBloco++){
            if(this.traceLRU[indiceBloco] == bloco){
                break;
            }
        }
        
        for(; indiceBloco < 3;indiceBloco++){
            this.traceLRU[indiceBloco] = this.traceLRU[indiceBloco+1];
        }
        
        this.traceLRU[3] = bloco;        
    }
    
    public int getBlocoFromLru(){
        return this.traceLRU[0];
    }

    @Override
    public String toString() {
        String s = "[";
        for(int i = 0; i < 4;i++){
            s += this.traceLRU[i] + ",";
        }
        s += "]\n";
        return s; //To change body of generated methods, choose Tools | Templates.
    }
    
    
    
}