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import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class BankGUI extends JFrame implements ActionListener {
private String[] NAME = new String[100]; // Resource names
private int[][] Max = new int[100][100]; // Maximum demand matrix
private int[][] Allocation = new int[100][100]; // Allocated resource matrix
private int[][] Need = new int[100][100]; // Remaining resource matrix
private int[] Available = new int[100]; // Available resource matrix
private int[] Request = new int[100]; // Request resource vector
private int[] Work = new int[100]; // Stores available resources in the system
private int[] Finish = new int[100]; // Marks whether the system has enough resources to allocate to each process
private int[] Security = new int[100]; // Stores the safety sequence
private int M = 100; // Maximum number of processes
private int N = 100; // Maximum number of resources
private int currentProcess; // Current process number
private JTextField[] txtAvailable;
private JTextField[] txtMax;
private JTextField[] txtAllocation;
private JTextField[] txtNeed;
private JTextField[] txtRequest;
private JButton btnRequest;
private JTextArea txtOutput;
public BankGUI() {
setTitle("Banker's Algorithm");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(800, 600);
setLocationRelativeTo(null);
JPanel panel = new JPanel();
panel.setLayout(new GridBagLayout());
GridBagConstraints constraints = new GridBagConstraints();
constraints.insets = new Insets(5, 5, 5, 5);
// Available resources panel
JPanel pnlAvailable = new JPanel();
pnlAvailable.setBorder(BorderFactory.createTitledBorder("Available Resources"));
pnlAvailable.setLayout(new GridLayout(1, N));
txtAvailable = new JTextField[N];
for (int i = 0; i < N; i++) {
txtAvailable[i] = new JTextField(3);
pnlAvailable.add(txtAvailable[i]);
}
constraints.gridx = 0;
constraints.gridy = 0;
constraints.gridwidth = 2;
panel.add(pnlAvailable, constraints);
// Process details panel
JPanel pnlProcess = new JPanel();
pnlProcess.setLayout(new GridBagLayout());
pnlProcess.setBorder(BorderFactory.createTitledBorder("Process Details"));
JPanel pnlLabels = new JPanel(new GridLayout(1, N));
for (int i = 0; i < N; i++) {
JLabel lblResource = new JLabel("Resource " + i);
pnlLabels.add(lblResource);
}
JPanel pnlMax = new JPanel(new GridLayout(M, N));
txtMax = new JTextField[M * N];
for (int i = 0; i < M * N; i++) {
txtMax[i] = new JTextField(3);
pnlMax.add(txtMax[i]);
}
JPanel pnlAllocation = new JPanel(new GridLayout(M, N));
txtAllocation = new JTextField[M * N];
for (int i = 0; i < M * N; i++) {
txtAllocation[i] = new JTextField(3);
pnlAllocation.add(txtAllocation[i]);
}
JPanel pnlNeed = new JPanel(new GridLayout(M, N));
txtNeed = new JTextField[M * N];
for (int i = 0; i < M * N; i++) {
txtNeed[i] = new JTextField(3);
pnlNeed.add(txtNeed[i]);
}
constraints.gridx = 0;
constraints.gridy = 0;
constraints.gridwidth = 1;
pnlProcess.add(pnlLabels, constraints);
constraints.gridx = 1;
constraints.gridy = 0;
pnlProcess.add(pnlMax, constraints);
constraints.gridx = 2;
constraints.gridy = 0;
pnlProcess.add(pnlAllocation, constraints);
constraints.gridx = 3;
constraints.gridy = 0;
pnlProcess.add(pnlNeed, constraints);
constraints.gridx = 0;
constraints.gridy = 1;
constraints.gridwidth = 4;
panel.add(pnlProcess, constraints);
// Resource request panel
JPanel pnlRequest = new JPanel();
pnlRequest.setBorder(BorderFactory.createTitledBorder("Resource Request"));
pnlRequest.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(5, 5, 5, 5);
JLabel lblProcess = new JLabel("Process Number:");
gbc.gridx = 0;
gbc.gridy = 0;
pnlRequest.add(lblProcess, gbc);
JComboBox cmbProcess = new JComboBox<>();
for (int i = 0; i < M; i++) {
cmbProcess.addItem("P" + i);
}
cmbProcess.addActionListener(e -> currentProcess = cmbProcess.getSelectedIndex());
gbc.gridx = 1;
gbc.gridy = 0;
pnlRequest.add(cmbProcess, gbc);
JPanel pnlResource = new JPanel(new GridLayout(1, N));
for (int i = 0; i < N; i++) {
JTextField txtResource = new JTextField(3);
txtRequest[i] = txtResource;
pnlResource.add(txtResource);
}
gbc.gridx = 0;
gbc.gridy = 1;
gbc.gridwidth = 2;
pnlRequest.add(pnlResource, gbc);
btnRequest = new JButton("Request");
btnRequest.addActionListener(this);
gbc.gridx = 0;
gbc.gridy = 2;
gbc.gridwidth = 2;
pnlRequest.add(btnRequest, gbc);
constraints.gridx = 0;
constraints.gridy = 2;
constraints.gridwidth = 2;
panel.add(pnlRequest, constraints);
// Output area
txtOutput = new JTextArea(10, 60);
txtOutput.setEditable(false);
JScrollPane scrollPane = new JScrollPane(txtOutput);
constraints.gridx = 0;
constraints.gridy = 3;
constraints.gridwidth = 4;
panel.add(scrollPane, constraints);
add(panel);
}
public void init() {
int i, j, m, n;
int number;
boolean flag;
String name;
int[] temp = new int[100];
// Input system resources and their initial quantities
n = N;
for (i = 0; i < n; i++) {
name = JOptionPane.showInputDialog("Resource " + i + " Name:");
NAME[i] = name;
number = Integer.parseInt(JOptionPane.showInputDialog("Resource " + name + " Initial Quantity:"));
Available[i] = number;
}
// Input number of processes and the maximum demand matrix
m = M;
System.out.println("Enter the maximum demand matrix [Max]:");
do {
flag = false;
for (i = 0; i < M; i++) {
for (j = 0; j < N; j++) {
Max[i][j] = Integer.parseInt(JOptionPane.showInputDialog("Max[" + i + "][" + j + "]:"));
if (Max[i][j] > Available[j]) {
flag = true;
}
}
}
if (flag) {
JOptionPane.showMessageDialog(null, "The maximum demand exceeds the maximum quantity of resources in the system. Please enter again!");
}
} while (flag);
// Input the allocated resources for each process and calculate the remaining needed resources
do {
flag = false;
for (i = 0; i < M; i++) {
for (j = 0; j < N; j++) {
Allocation[i][j] = Integer.parseInt(JOptionPane.showInputDialog("Allocation[" + i + "][" + j + "]:"));
if (Allocation[i][j] > Max[i][j]) {
flag = true;
}
Need[i][j] = Max[i][j] - Allocation[i][j];
temp[j] += Allocation[i][j];
}
}
if (flag) {
JOptionPane.showMessageDialog(null, "The allocated resources exceed the maximum quantity. Please enter again!");
}
} while (flag);
// Calculate the available resources in the system
for (j = 0; j < N; j++) {
Available[j] = Available[j] - temp[j];
}
}
public void showData() {
txtOutput.append("System Available Resources [Available]:\n");
for (int i = 0; i < N; i++) {
txtOutput.append(NAME[i] + " ");
}
txtOutput.append("\n");
for (int j = 0; j < N; j++) {
txtOutput.append(Available[j] + " ");
}
txtOutput.append("\n");
txtOutput.append("Current Resource Allocation:\n");
txtOutput.append(" Max Allocation Need\n");
txtOutput.append("Process ");
for (int j = 0; j < 3; j++) {
for (int i = 0; i < N; i++) {
txtOutput.append(NAME[i] + " ");
}
txtOutput.append(" ");
}
txtOutput.append("\n");
for (int i = 0; i < M; i++) {
txtOutput.append("P" + i + " ");
for (int j = 0; j < N; j++) {
txtOutput.append(Max[i][j] + " ");
}
txtOutput.append(" ");
for (int j = 0; j < N; j++) {
txtOutput.append(Allocation[i][j] + " ");
}
txtOutput.append(" ");
for (int j = 0; j < N; j++) {
txtOutput.append(Need[i][j] + " ");
}
txtOutput.append("\n");
}
}
public void test(int i) {
for (int j = 0; j < N; j++) {
Available[j] = Available[j] - Request[j];
Allocation[i][j] = Allocation[i][j] + Request[j];
Need[i][j] = Need[i][j] - Request[j];
}
}
public void retest(int i) {
for (int j = 0; j < N; j++) {
Available[j] = Available[j] + Request[j];
Allocation[i][j] = Allocation[i][j] - Request[j];
Need[i][j] = Need[i][j] + Request[j];
}
}
public boolean isSafe() {
int[] work = new int[N];
int[] finish = new int[M];
int[] security = new int[M];
int k = 0;
int count = 0;
int i, j;
for (i = 0; i < N; i++) {
work[i] = Available[i];
}
for (i = 0; i < M; i++) {
finish[i] = 0;
}
while (count < M) {
for (i = 0; i < M; i++) {
if (finish[i] == 0) {
for (j = 0; j < N; j++) {
if (Need[i][j] > work[j]) {
break;
}
}
if (j == N) {
for (int m = 0; m < N; m++) {
work[m] = work[m] + Allocation[i][m];
}
security[k++] = i;
finish[i] = 1;
count++;
}
}
}
}
if (count == M) {
txtOutput.append("System is in a safe state.\n");
txtOutput.append("Safe sequence is: ");
for (i = 0; i < M - 1; i++) {
txtOutput.append("P" + security[i] + " -> ");
}
txtOutput.append("P" + security[M - 1] + "\n");
return true;
} else {
txtOutput.append("System is in an unsafe state.\n");
return false;
}
}
@Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == btnRequest) {
for (int i = 0; i < N; i++) {
Request[i] = Integer.parseInt(txtRequest[i].getText());
}
if (isSafe()) {
test(currentProcess);
if (isSafe()) {
txtOutput.append("Request can be granted!\n");
txtOutput.append("New Resource Allocation:\n");
txtOutput.append(" Max Allocation Need\n");
txtOutput.append("Process ");
for (int j = 0; j < 3; j++) {
for (int i = 0; i < N; i++) {
txtOutput.append(NAME[i] + " ");
}
txtOutput.append(" ");
}
txtOutput.append("\n");
txtOutput.append("P" + currentProcess + " ");
for (int j = 0; j < N; j++) {
txtOutput.append(Max[currentProcess][j] + " ");
}
txtOutput.append(" ");
for (int j = 0; j < N; j++) {
txtOutput.append(Allocation[currentProcess][j] + " ");
}
txtOutput.append(" ");
for (int j = 0; j < N; j++) {
txtOutput.append(Need[currentProcess][j] + " ");
}
txtOutput.append("\n");
} else {
retest(currentProcess);
txtOutput.append("Request cannot be granted! It will cause an unsafe state.\n");
}
} else {
txtOutput.append("Request cannot be granted! It will cause an unsafe state.\n");
}
txtOutput.append("\n");
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
BankGUI gui = new BankGUI();
gui.init();
gui.showData();
gui.setVisible(true);
});
}
}
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