Java操作系统磁盘调度算法

package dianti; import java.util.ArrayList; import java.util.Arrays; public class Main { final static String direct = "R";//L代表向左，R代表向右 final static int startIndex = 30; //磁头位置 static ArrayList<Integer> discList = new ArrayList<Integer>(); static int[] discs = new int[] { 35,120,64,95,122,180,68,10 }; public static void main(String []args){ for (int i = 0; i < discs.length; i++) { discList.add(discs[i]); } discList.add(startIndex); Integer []temp = discList.toArray(new Integer[0]); Arrays.sort(temp); //对新数组从小到大进行排序 discList.clear(); for(int i = 0;i<temp.length;i++){ discList.add(temp[i]); } int discNumber = 0; int index = discList.indexOf(startIndex); //记录下开始的磁道数的索引 int maxindex = discList.size()-1;//最右的磁道索引 int minindex = 0;//最左的磁道索引 if(index == minindex){ for(int i = 0;i<discList.size();i++){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i>0){ discNumber+= Math.abs(discList.get(i)-discList.get(i-1)); } } System.out.println("访问总磁道数为"+discNumber); }else if(index == maxindex){ for(int i = maxindex;i>=0;i++){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i<maxindex){ discNumber+= Math.abs(discList.get(i)-discList.get(i+1)); } } System.out.println("访问总磁道数为"+discNumber); }else if(direct.equals("R") ){ for(int i = index;i<discList.size();i++){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i>index){ discNumber+= Math.abs(discList.get(i)-discList.get(i-1)); } } discNumber+= Math.abs(discList.get(index-1) - discList.get(maxindex)); for(int i = index-1;i>=0;i--){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i<index-1){ discNumber+= Math.abs(discList.get(i)-discList.get(i+1)); } } System.out.println("访问总磁道数为"+discNumber); }else if(direct.equals("L")){ for(int i = index;i>=0;i--){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i<index){ discNumber+= Math.abs(discList.get(i)-discList.get(i+1)); } } discNumber+= Math.abs(discList.get(index+1) - discList.get(minindex)); for(int i = index+1;i<discList.size();i++){ System.out.println("访问了"+discList.get(i)+"号磁道"); if(i>index+1){ discNumber+= Math.abs(discList.get(i)-discList.get(i-1)); } } System.out.println("访问总磁道数为"+discNumber); } } }