The entering() method of a Logger class used to Log a method entry.
There are three types of entering() method depending upon the parameters passed.
- entering(String sourceClass, String sourceMethod): This method is used to Log a method entry.Actually many times in application development we need to log when we enter in a method of class so this is a convenience method that can be used to log entry to a method. This method logs with message “ENTRY”, log level FINER, and the given sourceMethod and sourceClass are also logged.
Syntax:
public void entering(String sourceClass, String sourceMethod)
Parameters: This method accepts two parameters:
- sourceClass is the name of the class that issued the logging request and
- sourceMethod is the name of the method that is being entered.
Return value: This method returns nothing.
Below program illustrate entering(String sourceClass, String sourceMethod) method:
Program 1:// Java program to demonstrate
// entering(String, String) method
import
java.io.IOException;
import
java.util.List;
import
java.util.logging.*;
public
class
GFG {
public
static
void
main(String[] args)
throws
SecurityException, IOException
{
// Create a Logger
Logger logger
= Logger.getLogger(
GFG.
class
.getName());
// Create a file handler object
FileHandler handler
=
new
FileHandler(
"logs.txt"
);
handler.setFormatter(
new
SimpleFormatter());
// Add file handler as
// handler of logs
logger.addHandler(handler);
// set Logger level()
logger.setLevel(Level.FINER);
// call entering methods with class
// name = GFG and method name = main
logger.entering(GFG.
class
.getName(),
"main"
);
// calling again for List class toString()
logger.entering(List.
class
.getName(),
"toString()"
);
}
}
The output printed on log.txg file is shown below.
Output: - entering(String sourceClass, String sourceMethod, Object param1): This method is used to Log a method entry, with one parameter where parameter passed is an object we want to log. Actually many times in application development we need to log when we enter in a method of class so this is a convenience method that can be used to log entry to a method. This method logs with message “ENTRY {0}”, log level FINER, and the given sourceMethod, sourceClass, and parameter are logged.
Syntax:
public void entering(String sourceClass, String sourceMethod, Object param1)
Parameters: This method accepts three parameters:
- sourceClass is the name of the class that issued the logging request and
- sourceMethod is the name of the method that is being entered.
- param1: is the parameter to the method being entered.
Return value: This method returns nothing.
Below programs illustrate entering(String sourceClass, String sourceMethod, Object param1) method:
Program 1:
// Java program to demonstrate
// entering(String, String, Object) method
import
java.io.IOException;
import
java.util.logging.*;
public
class
GFG {
public
static
void
main(String[] args)
throws
SecurityException, IOException
{
// Create a Logger
Logger logger
= Logger.getLogger(
GFG.
class
.getName());
// Create a file handler object
FileHandler handler
=
new
FileHandler(
"logs.txt"
);
handler.setFormatter(
new
SimpleFormatter());
// Add file handler as
// handler of logs
logger.addHandler(handler);
// set Logger level()
logger.setLevel(Level.FINER);
// call entering method with class
// name = GFG and method name = main
logger.entering(
GFG.
class
.getName(),
"main"
,
new
String(
"Java is Platform Independent"
));
}
}
The output printed on log.txt is shown below.
-
entering(String sourceClass, String sourceMethod, Object[] params): This method is used to Log a method entry, with an array of parameters. Actually many times in application development we need to log when we enter in a method of class so this is a convenience method that can be used to log entry to a method. This method logs with message “ENTRY” (followed by a format {N} indicator for each entry in the parameter array), log level FINER, and the given sourceMethod, sourceClass, and parameter are logged.
Syntax:
public void entering(String sourceClass, String sourceMethod, Object[] params)
Parameters: This method accepts three parameters:
- sourceClass is the name of the class that issued the logging request and
- sourceMethod is the name of the method that is being entered.
- params: is an array of parameters to the method being entered.
Return value: This method returns nothing.
Below programs illustrate entering(String sourceClass, String sourceMethod, Object[] params) method:
Program 1:// Java program to demonstrate
// entering(String, String, Object[]) method
import
java.io.IOException;
import
java.util.logging.*;
public
class
GFG {
public
static
void
main(String[] args)
throws
SecurityException, IOException
{
// Create a Logger
Logger logger
= Logger.getLogger(
GFG.
class
.getName());
// Create a file handler object
FileHandler handler
=
new
FileHandler(
"logs.txt"
);
handler.setFormatter(
new
SimpleFormatter());
// Add file handler as
// handler of logs
logger.addHandler(handler);
// set Logger level()
logger.setLevel(Level.FINER);
// create a array of String object
String[] methods = {
"main"
,
"ADD"
,
"get"
,
"set"
};
// call entering method with class
// name = GFG and method name = main
logger.entering(GFG.
class
.getName(),
"main"
,
methods);
}
}
The output printed on log.txt is shown below.
References:
- https://docs.oracle.com/javase/10/docs/api/java/util/logging/Logger.html#entering(java.lang.String, java.lang.String)
- https://docs.oracle.com/javase/10/docs/api/java/util/logging/Logger.html#entering(java.lang.String, java.lang.String, java.lang.Object)
- https://docs.oracle.com/javase/10/docs/api/java/util/logging/Logger.html#entering(java.lang.String, java.lang.String, java.lang.Object%5B%5D)