Client-Server Communication in C: Examples and Code

Posted by on Jan 4, 2025 in Computers | 0 comments

Client Program Example (AF_INET, Stream)

This is an example of a client program using the AF_INET family type and stream sockets that sends messages to a server program. The functions leer_linea and escribir_linea are assumed to be defined in the file comun.c.


void escribir_mensaje(int s);

int main() {
    int sd;
    struct sockaddr_in dirser;

    if ((sd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
        perror("Error creating socket");
        return 1;
    }

    dirser.sin_family = AF_INET;
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Java AWT Components: Buttons, Lists, Text Fields, and More

Posted by on Jan 3, 2025 in Computers | 0 comments

Buttons

Buttons can be created with objects using the operator new:

Button button; button = new Button("Button");

Used in CADNA creation, the button will appear when displayed on the screen. This is also what CADNA will return to use when identifying the button event.

Button Events

One-touch button events can be captured by overloading the method action():

public boolean action(Event evt, Object obj) {
    if (evt.target instanceof Button)
        System.out.println((String) obj);
    else

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Database Schema and Queries for Hockey League

Posted by on Jan 3, 2025 in Computers | 0 comments

Table Structures

Equipo Table

— Table structure for table Equipo

DROP TABLE IF EXISTS Equipo;

CREATE TABLE Equipo (

team_id int(11) NOT NULL,

teamName varchar(45) DEFAULT NULL,

PRIMARY KEY (team_id)

Estadísticas_Equipo Table

— Table structure for table Estadísticas_Equipo

DROP TABLE IF EXISTS Estadísticas_Equipo;

CREATE TABLE Estadísticas_Equipo (

game_id int(11) NOT NULL,

team_id int(11) NOT NULL,

tgoals int(11) DEFAULT NULL,

tshots int(11) DEFAULT NULL,

thits int(11) DEFAULT NULL,

PRIMARY KEY (game_id,team_

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Java Person and Pet Management Code

Posted by on Jan 3, 2025 in Computers | 0 comments

Java Person and Pet Management

This Java code provides functionality to manage a list of people and their pets. It includes methods to create, read, update, and delete person records.

Create Person

The createPerson() method allows you to add a new person to the list. It prompts for the person’s name, age, and gender, and allows adding pets to the person’s record.

public static void createPerson() {
    String name = WordNotEmpty("Enter name:");
    if (getPersonByName(name) != null) {
        System.
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Firewall Technologies: Packet Filtering, Proxy, and Stateful Inspection

Posted by on Jan 3, 2025 in Computers | 0 comments

Firewall Technologies

Packet filtering – Packets (small chunks of data) are analyzed against a set of filters. Packets that pass the filters are sent to the requesting system; all others are discarded.

Proxy service – Information from the Internet is retrieved by the firewall and then sent to the requesting system and vice versa.

Stateful inspection – A newer method that doesn’t examine the contents of each packet but instead compares certain key parts of the packet to a database of trusted information.

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Java Code Snippets: Database, Lambda, and String Operations

Posted by on Jan 3, 2025 in Computers | 0 comments

Database URL: jdbc:mysql://mis-sql.uhcl.edu/agarwaln8497

Database username: agarwaln8497
Database password: 1005681
Error message: String errorMsg = "";
Connection: Connection c = null;
Statement: Statement s = null;
ResultSet: ResultSet rset = null;

Submit Method

This method handles database connection and data retrieval.

    
      public String Submit() {
        try {
          Class.forName("com.mysql.jdbc.Driver");
          System.out.println("Driver is ok.");
        } catch (ClassNotFoundException
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