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# Logging
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Seamless integration with popular Java logging frameworks through automatic logger field generation.
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## Capabilities
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### SLF4J Integration
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```java { .api }
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface Slf4j {
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    String topic() default "";
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface XSlf4j {
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    String topic() default "";
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}
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```
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### Log4j Integration
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```java { .api }
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface Log4j {
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    String topic() default "";
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface Log4j2 {
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    String topic() default "";
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}
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```
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### Other Logging Frameworks
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```java { .api }
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface Log {  // Java Util Logging
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    String topic() default "";
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface CommonsLog {  // Apache Commons Logging
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    String topic() default "";
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface JBossLog {  // JBoss Logging
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    String topic() default "";
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface Flogger {  // Google Flogger
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}
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@Target(ElementType.TYPE)
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@Retention(RetentionPolicy.SOURCE)
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public @interface CustomLog {
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    String topic() default "";
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}
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```
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**Usage Examples:**
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```java
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import lombok.extern.slf4j.Slf4j;
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@Slf4j
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public class UserService {
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    public void createUser(String name) {
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        log.info("Creating user: {}", name);
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        // Implementation
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        log.debug("User created successfully");
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    }
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}
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// Generated field:
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// private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(UserService.class);
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```
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**Log4j2 Example:**
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```java
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import lombok.extern.log4j.Log4j2;
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@Log4j2
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public class PaymentProcessor {
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    public void processPayment(double amount) {
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        log.info("Processing payment of ${}", amount);
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        try {
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            // Payment processing logic
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            log.debug("Payment processed successfully");
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        } catch (Exception e) {
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            log.error("Payment processing failed", e);
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        }
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    }
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}
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// Generated field:
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// private static final org.apache.logging.log4j.Logger log = org.apache.logging.log4j.LogManager.getLogger(PaymentProcessor.class);
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```
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**Java Util Logging Example:**
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```java
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import lombok.extern.java.Log;
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@Log
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public class FileManager {
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    public void saveFile(String filename) {
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        log.info("Saving file: " + filename);
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        // Implementation
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        log.fine("File saved successfully");
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    }
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}
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// Generated field:
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// private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(FileManager.class.getName());
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```
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**Custom Topic Example:**
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```java
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import lombok.extern.slf4j.Slf4j;
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@Slf4j(topic = "AUDIT")
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public class AuditService {  
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    public void auditAction(String action) {
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        log.info("Audit: {}", action);
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    }
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}
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// Generated field:
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// private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger("AUDIT");
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```