Java Library Development Development common LOG framework issues and discharge techniques
Java Library Development Development common LOG framework issues and discharge techniques
During the development of the Java class library, the log record is an important part.By using the log framework, we can easily capture and record the operation information of the class library at runtime in order to check errors and debug.However, there may also be some common problems in the log frame itself. This article will introduce some common problems and errors, and provide corresponding Java code examples.
1. The problem that cannot be found or loaded the log framework
One of the most common cases is that the log framework that cannot be found or cannot be loaded in the application path of the application.This may be caused by the following reasons:
-Feng the relevant dependencies of the log framework to the construction file of the project (for example, using maven's pom.xml file).
-In use of multiple log frameworks, leading to conflict and loading failure.
To solve these problems, you can solve it by checking the dependence of the project and ensuring that only one log framework is used.At the same time, ensure that the relevant dependence of the log frame is loaded correctly.
2. Configuration problem
-Log -level settings are incorrect: During the development and debugging process, the log level may be set to debug in order to print more detailed information.However, in the production environment, the log level should be set to a higher level (such as INFO or Warn) to avoid generating too much useful log records.
-In the unable to redirect the log output to the required position: out of security or other reasons, you may need to redirect the log output to a specific position (such as file or database).When using the log frame, make sure the output target is correctly configured so that the log record is preserved to the required position.
-In the desired log format: Sometimes, you need to customize the format of the log in order to better meet the needs of the project.This may include information such as adding time stamps, names, and method names.Check the documents used by the log framework, understand how to customize the log format, and configure it accordingly.
3. Logging record efficiency problem
-In use string connection operation to perform log records: Frequent use of string connection operations in the log record may lead to decline in performance.This is because string connection operations can cause new String objects to consume memory and processing time.In order to improve the efficiency of log records, it is recommended to use the log framework that provides a parameter logging method (such as log.debug (String Format, Object ... Arguments) in Log4j), and pass the specific parameter to the log record method.
-For frequently logging: If the logging method frequently calls the log record method in a function of cycling or high -frequency calls, it may have a negative impact on performance.In this case, performance can be improved by setting an appropriate log level and restricting the frequency of log records to improve performance.
Below is a Java code example using log4j as a log frame:
import org.apache.log4j.Logger;
public class MyClass {
private static final Logger logger = Logger.getLogger(MyClass.class);
public void doSomething() {
logger.debug("Debug message");
logger.info("Info message");
logger.warn("Warning message");
logger.error("Error message");
}
}
In the above example, we use log4j to configure a class -level logger object.We can then use this Logger object to record different levels of log messages.
Summarize
In the development of the Java class library, log records are an important part that can help us track and debug problems in the class library.However, there may also be some common problems with the log framework, such as the unable to load log framework, configuration problems, and logging efficiency issues.By understanding and following the correct solution skills, we can better use the log framework and effectively check and solve the problem.
