银行家算法java实现

package Banker; import java.util.Scanner; public class Banker { int[] Available={10,5,7}; int[][] Max=new int[5][3]; int[][] Allocation = new int[5][3]; int[][] Need = new int[5][3]; int[][] Request = new int[5][3]; int[] Work = new int[3]; static int num = 0;//全局变量 表示进程编号 Scanner in = new Scanner(System.in); public Banker() { } public void initVariable() //初始化变量 { setMax(); setAllocation(); printSystemVariable(); SecurityAlgorithm(); } private void setAllocation() { System.out.println("请设置请各进程分配矩阵Alloction："); for (int i = 0; i < 5; i++) { System.out.println("请输入进程P" + i + "的分配资源量："); for (int j = 0; j < 3; j++) { Allocation[i][j] = in.nextInt(); } } System.out.println("Available=Available-Allocation."); System.out.println("Need=Max-Alloction."); for (int i = 0; i < 3; i++) {//设置Available矩阵 for (int j = 0; j < 5; j++) { Available[i] = Available[i] - Allocation[j][i]; } } for (int i = 0; i < 5; i++) {//设置Need矩阵 for (int j = 0; j < 3; j++) { Need[i][j] = Max[i][j] - Allocation[i][j]; } } } private void setMax() { System.out.println("请设置各进程的最大需求矩阵Max："); for (int i = 0; i < 5; i++) { System.out.println("请输入进程P" + i + "三类资源的最大资源需求量："); for (int j = 0; j < 3; j++) { Max[i][j] = in.nextInt(); } } } public void printSystemVariable(){ System.out.println("此时资源分配量如下："); System.out.println("进程 "+" Max "+" Alloction "+" Need "+" Available "); for(int i=0;i<5;i++) { System.out.print("P"+i+" "); for(int j=0;j<3;j++) { System.out.print(Max[i][j]+" "); } System.out.print("| "); for(int j=0;j<3;j++) { System.out.print(Allocation[i][j]+" "); } System.out.print("| "); for(int j=0;j<3;j++) { System.out.print(Need[i][j]+" "); } System.out.print("| "); if(i==0) { for(int j=0;j<3;j++) { System.out.print(Available[j]+" "); } } System.out.println(); } } public void setRequest() {//设置请求资源量Request System.out.println("请输入请求资源的进程编号："); num= in.nextInt();//设置全局变量进程编号num System.out.println("请输入请求各资源的数量："); for (int j = 0; j < 3; j++) { Request[num][j] = in.nextInt(); } System.out.println("即进程P" + num + "对各资源请求Request：(" + Request[num][0] + "," + Request[num][1] + "," + Request[num][2] + ")."); BankerAlgorithm(); } private void BankerAlgorithm() { boolean T = true; //标志位 if(Request[num][0]<=Need[num][0]&&Request[num][1]<=Need[num][1]&&Request[num][2]<=Need[num][2]) { //请求资源小于所需要的资源 if(Request[num][0] <= Available[0]&&Request[num][1] <= Available[1]&&Request[num][2] <= Available[2]) { for(int i = 0;i < 3;i++) { Available[i] -= Request[num][i]; Allocation[num][i] += Request[num][i]; Need[num][i] -= Request[num][i]; } } else { System.out.println("当前没有足够的资源可分配，进程P" + num + "需等待。"); T = false; } } else { System.out.println("进程P" + num + "请求已经超出最大需求量Need."); T=false; } if(T == true)//分配成功 安全检查 { printSystemVariable(); System.out.println("现在进入安全算法："); SecurityAlgorithm(); } } private void SecurityAlgorithm() { boolean[] Finish = {false,false,false,false,false};//初始化 int count = 0; //完成 进程数目 int circle = 0; //循环圈数 boolean flag = true; int[] S=new int[5];//存储当前的安全序列 for (int i = 0; i < 3; i++) {//设置工作向量 Work[i] = Available[i]; } while(count<5) { if(flag) { System.out.println("进程 "+" Work "+" Alloction "+" Need "+" Work+Alloction"); flag = false; } for (int i = 0; i < 5; i++) { if (Finish[i] == false&&Need[i][0] <= Work[0]&&Need[i][1] <= Work[1]&&Need[i][2] <= Work[2]) { //判断当前进程是否满足条件 count++;//足进程数加1满 Finish[i]=true;//当当前进程能满足时 S[count-1]=i;//设置当前序列排号 System.out.print("P"+i+" "); for (int k = 0; k < 3; k++) { System.out.print(Work[k]+" "); } System.out.print("| "); for (int j = 0; j<3;j++) { Work[j] += Allocation[i][j]; } for(int j=0;j<3;j++) { System.out.print(Allocation[i][j]+" "); } System.out.print("| "); for(int j=0;j<3;j++) { System.out.print(Need[i][j]+" "); } System.out.print("| "); for(int j=0;j<3;j++) { System.out.print(Work[j]+" "); } System.out.println(); } } circle++;//循环圈数加1 if(count == 5) {//判断是否满足所有进程需要 System.out.print("此时存在一个安全序列："); for (int i = 0; i<5;i++) {//输出安全序列 System.out.print("P"+S[i]+" "); } System.out.println("故当前可分配！"); break;//跳出循环 } if(count<circle) {//判断完成进程数是否小于循环圈数 count=7; System.out.println("当前系统处于不安全状态，故不存在安全序列。"); break;//跳出循环 } } } }