Add centralized configuration management module

design_patterns/configuration_management/config.yaml

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+global:
+  db_url: "jdbc:mysql://localhost:3306/main"
+  jwt_secret: "default_secret"
+  vault_key: "global_vault_key"
+
+services:
+  serviceA:
+    jwt_secret: "serviceA_secret"
+  serviceB:
+    db_url: "jdbc:postgresql://localhost:5432/serviceB"

design_patterns/configuration_management/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
+                             http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>com.thealgorithms</groupId>
+  <artifactId>configuration-management-example</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <properties>
+    <maven.compiler.release>21</maven.compiler.release>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.yaml</groupId>
+      <artifactId>snakeyaml</artifactId>
+      <version>2.1</version>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.14.1</version>
+        <configuration>
+          <release>${maven.compiler.release}</release>
+        </configuration>
+      </plugin>
+
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>exec-maven-plugin</artifactId>
+        <version>3.1.0</version>
+        <configuration>
+          <mainClass>org.thealgorithms.config.ExampleUsage</mainClass>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>

design_patterns/configuration_management/src/main/java/org/thealgorithms/config/ConfigLoader.java

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+package org.thealgorithms.config;
+
+import org.yaml.snakeyaml.Yaml;
+import java.io.InputStream;
+import java.util.Map;
+
+/**
+ * ConfigLoader reads configuration from a shared YAML file.
+ * It supports global and service-specific configurations.
+ */
+public class ConfigLoader {
+
+    private final Map<String, Object> config;
+
+    public ConfigLoader(String filename) {
+        Yaml yaml = new Yaml();
+        try (InputStream in = ConfigLoader.class.getClassLoader().getResourceAsStream(filename)) {
+            if (in == null) {
+                throw new IllegalArgumentException("Configuration file not found: " + filename);
+            }
+            config = yaml.load(in);
+        } catch (Exception e) {
+            throw new RuntimeException("Failed to load configuration: " + e.getMessage(), e);
+        }
+    }
+
+    /**
+     * Returns the value of a global config key.
+     */
+    public Object getGlobal(String key) {
+        Map<String, Object> global = (Map<String, Object>) config.get("global");
+        return global != null ? global.get(key) : null;
+    }
+
+    /**
+     * Returns a value for a specific service override.
+     */
+    public Object getServiceOverride(String service, String key) {
+        Map<String, Map<String, Object>> services =
+            (Map<String, Map<String, Object>>) config.get("services");
+        if (services == null || !services.containsKey(service)) {
+            return null;
+        }
+        return services.get(service).getOrDefault(key, getGlobal(key));
+    }
+}

design_patterns/configuration_management/src/main/java/org/thealgorithms/config/ExampleUsage.java

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+package org.thealgorithms.config;
+
+/**
+ * Demonstrates how to use ConfigLoader with a shared YAML file.
+ */
+public class ExampleUsage {
+    public static void main(String[] args) {
+        ConfigLoader loader = new ConfigLoader("config.yaml");
+
+        System.out.println("Global DB URL: " + loader.getGlobal("db_url"));
+        System.out.println("Service A JWT Secret: " + loader.getServiceOverride("serviceA", "jwt_secret"));
+        System.out.println("Service B DB URL: " + loader.getServiceOverride("serviceB", "db_url"));
+    }
+}