银行家算法(java swing)界面
2021-01-25 01:15
标签：cat event 循环 pen zab select location 说明 提示 1. 成功运行。 2. 申请成功后可以进行撤销。 3. 若未成功申请无法进行撤销操作。 4. 不安全，申请失败。 5. 设置Allocation比Max大时。 6. 在已经有Allocation时，想修改Max数据，为了防止出错。 7. 成功设置Max。 8. 成功设置Allocation。 9. 成功设置Available。 银行家算法(java swing)界面 标签：cat event 循环 pen zab select location 说明 提示 原文地址：https://www.cnblogs.com/shish/p/12863583.html代码
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class BankerSwing {
JFrame jf = new JFrame("银行家算法");
JPanel jp1 = new JPanel();
JTextField jtf1, jtf2, jtf3, jtf4;
JComboBox jcb1;
JButton jb1, jb2, jb3, jb4;
JTextArea jta1;
private int numResource = 3;
private int numThread = 100;
private int p = 0; // 当前处理的线程
int[] Available = new int[numResource]; // 空闲资源
int[][] Max = new int[numThread][numResource]; // 最大需求资源
int[][] Allocation = new int[numThread][numResource]; // 占有资源
int[][] Need = new int[numThread][numResource]; // 需求资源
int[][] Request = new int[numThread][numResource]; // 申请资源
int[] Work = new int[numResource]; // 辅助空间
// 结果展示
public void ShowFrame(){
jf.setSize(530, 350); //大小
jf.setAlwaysOnTop(true);
jf.setResizable(false);//不可拖动
jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
// 初始化
jtf1 = new JTextField(3);
jtf2 = new JTextField(3);
jtf3 = new JTextField(3);
jtf4 = new JTextField(3);
String s[] = {"Max","Allocation","Available","Request"};
jcb1 = new JComboBox(s);
jb1 = new JButton("确定");
jb2 = new JButton("例子");
jb3 = new JButton("清零");
jb4 = new JButton("撤销");
// 底部布局
jp1.add(jcb1);
jp1.add(new JLabel("ID:"));
jp1.add(jtf1);
jp1.add(new JLabel("A:"));
jp1.add(jtf2);
jp1.add(new JLabel("B:"));
jp1.add(jtf3);
jp1.add(new JLabel("C:"));
jp1.add(jtf4);
jp1.add(jb1);
jb1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == jb1) {
if(jcb1.getSelectedItem() == "Allocation"){//设置已占用资源
try{
p = Integer.parseInt(jtf1.getText());
if (p > 4) {
JOptionPane.showMessageDialog(jf, "进程ID在0-4之间！","提示",JOptionPane.WARNING_MESSAGE);
jtf1.setText("");
return;
}
if (Integer.parseInt(jtf2.getText()) ) {
JOptionPane.showMessageDialog(jf, "资源数不能小于0！", "提示", JOptionPane.WARNING_MESSAGE);
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
if(Integer.parseInt(jtf2.getText()) > Max[p][0] || Integer.parseInt(jtf3.getText()) > Max[p][1] || Integer.parseInt(jtf4.getText()) > Max[p][2]){
JOptionPane.showMessageDialog(jf, "占用资源大于最大需求资源(未定义最大需求资源)", "提示", JOptionPane.WARNING_MESSAGE);
jtf1.setText("");
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
Allocation[p][0] = Integer.parseInt(jtf2.getText());
Need[p][0] = Max[p][0] - Allocation[p][0];
Allocation[p][1] = Integer.parseInt(jtf3.getText());
Need[p][1] = Max[p][1] - Allocation[p][1];
Allocation[p][2] = Integer.parseInt(jtf4.getText());
Need[p][2] = Max[p][2] - Allocation[p][2];
} catch(Exception d) {
JOptionPane.showMessageDialog(jf, "输入有误！请重新输入！", "提示", JOptionPane.WARNING_MESSAGE);
ShowData();
return;
}
ShowData();
jta1.append("\n\n 已占有资源设置成功！");
} else if (jcb1.getSelectedItem() == "Max") {
try {
p = Integer.parseInt(jtf1.getText());
if (p > 4) {
JOptionPane.showMessageDialog(jf, "进程ID在0-4之间！", "提示", JOptionPane.WARNING_MESSAGE);
jtf1.setText("");
return;
}
if (Integer.parseInt(jtf2.getText()) ) {
JOptionPane.showMessageDialog(jf, "资源数不能小于0！", "提示", JOptionPane.WARNING_MESSAGE);
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
if(Integer.parseInt(jtf2.getText()) ]){
JOptionPane.showMessageDialog(jf, "最大需求资源小于已占有资源！", "提示", JOptionPane.WARNING_MESSAGE);
jtf1.setText("");
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
Max[p][0] = Integer.parseInt(jtf2.getText());
Need[p][0] = Max[p][0] - Allocation[p][0];
Max[p][1] = Integer.parseInt(jtf3.getText());
Need[p][1] = Max[p][1] - Allocation[p][1];
Max[p][2] = Integer.parseInt(jtf4.getText());
Need[p][2] = Max[p][2] - Allocation[p][2];
} catch(Exception d) {
JOptionPane.showMessageDialog(jf, "输入有误！请重新输入！", "提示", JOptionPane.WARNING_MESSAGE);
ShowData();
return;
}
ShowData();
jta1.append("\n\n 最大需求设置成功！");
} else if (jcb1.getSelectedItem()=="Available"){//设置可用资源
try{
if (Integer.parseInt(jtf2.getText()) ) {
JOptionPane.showMessageDialog(jf, "资源数不能小于0！", "提示", JOptionPane.WARNING_MESSAGE);
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
Available[0] = Integer.parseInt(jtf2.getText());
Available[1] = Integer.parseInt(jtf3.getText());
Available[2] = Integer.parseInt(jtf4.getText());
}catch(Exception d) {
JOptionPane.showMessageDialog(jf, "您输入有误！请重新输入！", "提示", JOptionPane.WARNING_MESSAGE);
ShowData();
return;
}
ShowData();
jta1.append("\n\n 可用资源设置成功！");
} else if(jcb1.getSelectedItem() == "Request"){
try{
p = Integer.parseInt(jtf1.getText());
if (p > 4) {
JOptionPane.showMessageDialog(jf, "进程ID在0-4之间！", "提示", JOptionPane.WARNING_MESSAGE);
jtf1.setText("");
return;
}
if (Integer.parseInt(jtf2.getText()) ) {
JOptionPane.showMessageDialog(jf, "资源数不能小于0！", "提示", JOptionPane.WARNING_MESSAGE);
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
return;
}
Request[p][0] = Integer.parseInt(jtf2.getText());
Request[p][1] = Integer.parseInt(jtf3.getText());
Request[p][2] = Integer.parseInt(jtf4.getText());
}catch(Exception d) {
JOptionPane.showMessageDialog(jf, "您输入有误！请重新输入！", "提示", JOptionPane.WARNING_MESSAGE);
ShowData();
return;
}
int[] order = new int[numThread];
if(bankerKernel(p, order)){
ShowData();
jta1.append("\n\n 通过安全性检查！安全序列为：");
for(int i = 0; i //打印安全序列
jta1.append("P"+order[i]+" ");
JOptionPane.showMessageDialog(jf, "申请成功，资源已经分配~~~","提示",JOptionPane.INFORMATION_MESSAGE);
}else {
ShowData();
for (int i = 0; i ) {
Request[p][i] = 0;
}
JOptionPane.showMessageDialog(jf, "找不到安全序列！ 不批准请求！", "提示", JOptionPane.WARNING_MESSAGE);
}
}else{
ShowData();
jta1.append("\n\n 系统资源不足！");
}
}
}
}); // 确定按键功能设定
jp1.setBackground(new java.awt.Color(128,255,128));
// 右边布局，竖直
Box vBox = Box.createVerticalBox();
vBox.add(Box.createVerticalStrut(60)); // 添加空白
vBox.add(jb2);
vBox.add(Box.createVerticalStrut(20)); // 添加空白
vBox.add(jb3);
vBox.add(Box.createVerticalStrut(20)); // 添加空白
vBox.add(jb4);
jb2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == jb2){
init();
ShowData();
}
}
}); // 例子按键功能设定
jb3.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == jb3){
reset();
ShowData();
}
}
}); // 清零按键功能设定
jb4.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == jb4){
if(revocation())
JOptionPane.showMessageDialog(jf, "撤销成功~~~","提示", JOptionPane.INFORMATION_MESSAGE);
else
JOptionPane.showMessageDialog(jf, "无撤销内容！","提示", JOptionPane.WARNING_MESSAGE);
ShowData();
}
}
}); // 撤销按键功能设定
jf.add(jp1,"South"); // 布局底部
jf.add(vBox,"After");// 右边
// 展示中间的文本
jta1= new JTextArea();
ShowData();
jta1.setLineWrap(true);
jta1.setBackground(Color.white);
jta1.setEditable(false);
jf.add(jta1,BorderLayout.CENTER);
// 结果展示
jf.setVisible(true);
}
// 展示数据
public void ShowData() {
jta1.setText(" Max \tAllocation \t Need Available\n");
jta1.append("\n" + " 资源 " + " A B C " + " A B C " +
" A B C " + " A B C");
jta1.append("\n 进程\n P0" + " " +
+ Max[0][0] + " " + Max[0][1] + " "
+Max[0][2] + " " +
" " + Allocation[0][0] + " " + Allocation[0][1]
+ " " + Allocation[0][2] + " " +
" " + Need[0][0] + " " + Need[0][1]
+ " " + Need[0][2] + " " +
" " + Available[0] + " " + Available[1] +
" " + Available[2]);
for (int i = 1; i ) {
jta1.append("\n\n P" + i + " " +
" " + Max[i][0] + " " + Max[i][1] + " " + Max[i][2] + " " +
" " + Allocation[i][0] + " " + Allocation[i][1]
+ " " + Allocation[i][2] + " " +
" " + Need[i][0] + " " + Need[i][1]
+ " " + Need[i][2] + " ");
}
jtf1.setText("");
jtf2.setText("");
jtf3.setText("");
jtf4.setText("");
}
// 算法核心流程
public boolean bankerKernel(int num, int[] order){
// 判断资源申请的数量是否符合空闲资源和需要资源
for(int i = 0; i ){
if(Request[num][i] > Need[num][i]) {
System.out.println("错误：进程P" + num + "的申请，超出最大需求量Need。");
return false;
}
else if(Request[num][i] > Available[i]){
System.out.println("错误：当前没有足够的资源可申请，进程P" + num + "需等待。");
return false;
}
}
// 更新空闲资源，占用资源和需要资源
for (int i = 0; i ) {
Allocation[num][i] += Request[num][i];
Available[i] -= Request[num][i];
Need[num][i] -= Request[num][i];
}
// 安全性检查
if(isSafe(order)){
return true;
}
// 不安全，返回申请资源前的状态
for (int i = 0; i ) {
Allocation[num][i] -= Request[num][i];
Available[i] += Request[num][i];
Need[num][i] += Request[num][i];
}
return false;
}
// 安全性检查
public boolean isSafe(int[]order){
int count = 0; // 安全的线程数量
int k = 0;
int circle = 0; // 循环次数
boolean[] Finish = new boolean[numThread]; // 线程是否进入安全序列
for (int i = 0; i ) {
Finish[i] = false;
}
copyWork();
while(true){
for (int i = 0; i ) {
if(Finish[i] == false){
for (k = 0; k ) {
if(Work[k] Need[i][k])
break;
}
// 空闲资源满足线程所需要的资源
if(k == numResource){
order[count++] = i;
Finish[i] = true;
// 释放资源
for (int j = 0; j ) {
Work[j] += Allocation[i][j];
}
}
}
}
circle++;
if(count == numThread){
System.out.print("存在一个安全序列：");
for (int i = 0; i //输出安全序列
System.out.print("P" + order[i] + " ");
}
System.out.println("故当前可分配！");
return true;
}
// 如果进入安全序列的线程数小于循环次数，说明不存在能安全完成的线程
if(count circle){
System.out.println("警告：申请使得系统处于不安全状态，申请失败。");
return false;
}
}
}
// 使用辅助空间
public void copyWork(){
for (int i = 0; i ) {
Work[i] = Available[i];
}
}
// 初始化一个例子
public void init(){
numThread = 5;
numResource = 3;
Available[0] = 3; Available[1] = 3; Available[2] = 2;
Max[0][0] = 7; Max[0][1] = 5; Max[0][2] = 3;
Max[1][0] = 3; Max[1][1] = 2; Max[1][2] = 2;
Max[2][0] = 9; Max[2][1] = 0; Max[2][2] = 2;
Max[3][0] = 2; Max[3][1] = 2; Max[3][2] = 2;
Max[4][0] = 4; Max[4][1] = 3; Max[4][2] = 3;
Allocation[0][0] = 0; Allocation[0][1] = 1; Allocation[0][2] = 0;
Allocation[1][0] = 2; Allocation[1][1] = 0; Allocation[1][2] = 0;
Allocation[2][0] = 3; Allocation[2][1] = 0; Allocation[2][2] = 2;
Allocation[3][0] = 2; Allocation[3][1] = 1; Allocation[3][2] = 1;
Allocation[4][0] = 0; Allocation[4][1] = 0; Allocation[4][2] = 2;
for (int i = 0; i ) {
for (int j = 0; j ) {
Need[i][j] = Max[i][j] - Allocation[i][j];
}
}
}
// 清零
public void reset(){
for (int i = 0; i ) {
for (int j = 0; j ) {
Max[i][j] = 0;
Allocation[i][j] = 0;
Need[i][j] = 0;
Available[j] = 0;
}
}
}
// 撤回
public boolean revocation(){
if(Request[p][0] == 0 && Request[p][1] == 0 && Request[p][2] == 0)
return false;
for (int i = 0; i ) {
Allocation[p][i] -= Request[p][i];
Need[p][i] = Max[p][i] - Allocation[p][i];
Available[i] += Request[p][i];
Request[p][i] = 0;
}
return true;
}
public static void main(String[] args) {
BankerSwing B = new BankerSwing();
B.ShowFrame();
}
}
结果截图
上一篇：python字符串详解
下一篇：KMP 算法的两种实现
文章标题：银行家算法(java swing)界面
文章链接：http://soscw.com/index.php/essay/46572.html