java 使用Java 8 lambdas编写干净的日志代码

Posted 2021-05-08

import lombok.extern.log4j.Log4j2;

@Log4j2 
public class CSysFormular {

  public void preJava8() {
    
    String parameter1 = "test";
    // Log only if log level equal or above debug
    if (logger.isDebugEnabled()) {
      logger.debug("Logentry Parameters {} {} ", parameter1, costlyOperation());
    }  
 }
 
 public void Java8() {
    
    String parameter1 = "test";
    //parameter1 and costlyOperation are only evaluated if loglevel equal or above debug 
    logger.debug("Logentry Parameters {} {} ", () -> parameter1, ()->costlyOperation());  
 }
 
 public String costlyOperation() {
   return "";
 }
}