JAMonInterceptor (JAMon Core 2.81 API)

java.lang.Object
- com.jamonapi.aop.general.JAMonInterceptor

Direct Known Subclasses:

JAMonEJBInterceptor
```
public class JAMonInterceptor
extends Object
```
JAMon Interceptor for measuring method execution time, and tracking any exceptions the method calls: can be used in EJB, or CDI in general. Note when an exception occurs several exception monitors are created from very general (com.jamonapi.Exceptions) to specific (for example com.mypackage.MyException). Also a 'detail' data string is created so more context can be viewed when an exception is thrown. The 'detail' contains the method name, stacktrace, and optionally (enabled by deafault) all of the method parameter names and values.

Field Summary

Fields
Modifier and Type	Field and Description
`protected static int`	`DEFAULT_ARG_STRING_MAX_LENGTH` Maximum length for a parameter in the exception dump
`protected static String`	`DEFAULT_MAX_STRING_ENDING` Parameters kept in the details section are capped at a max length and this string is put at the end of the string after the truncation point to indicate there is more data that is not shown.
`protected static String`	`EXCEPTION_UNITS` Exception units
`protected String`	`exceptionLabel` JAMon exception label - can be overridden in subclasses.
`protected static String`	`LINE_SEPARATOR`
`protected static String`	`MONITOR_PREFIX`
`protected static String`	`NULL_STR` Returned when a method parameter is null
`protected static String`	`UNKNOWN` used when a value isn't returned, and yet we don't want to throw an exception (hey it's just monitoring)

Constructor Summary

Constructors
Modifier Constructor and Description

JAMonInterceptor()

protected JAMonInterceptor(String exceptionLabel)

Constructors
Modifier	Constructor and Description
	`JAMonInterceptor()`
`protected`	`JAMonInterceptor(String exceptionLabel)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected String`	`createExceptionDetails(String label, Object[] parameters, Exception exception)` Default exception handling.
`protected String`	`getJamonLabel(javax.interceptor.InvocationContext ctx)` Returns JAMon's label for the specified Invocation context.
`Object`	`intercept(javax.interceptor.InvocationContext ctx)` Decorates method calls by monitoring them for performance and exceptions
`protected boolean`	`isMonitored(javax.interceptor.InvocationContext ctx)` Indicates whether the method invocation should be monitored.
`protected String`	`onException(javax.interceptor.InvocationContext ctx, String label, Exception exception)` Default exception handling.
`JAMonInterceptor`	`setUseParametersInDetails(boolean useParametersInDetails)`
`protected String`	`toString(Object parameter)` Turns a single method parameter into a string.
`boolean`	`useParametersInDetails()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - EXCEPTION_UNITS
```
protected static final String EXCEPTION_UNITS
```
    Exception units
    
    See Also:
    
    Constant Field Values
  - NULL_STR
```
protected static final String NULL_STR
```
    Returned when a method parameter is null
    
    See Also:
    
    Constant Field Values
  - UNKNOWN
```
protected static final String UNKNOWN
```
    used when a value isn't returned, and yet we don't want to throw an exception (hey it's just monitoring)
    
    See Also:
    
    Constant Field Values
  - DEFAULT_ARG_STRING_MAX_LENGTH
```
protected static final int DEFAULT_ARG_STRING_MAX_LENGTH
```
    Maximum length for a parameter in the exception dump
    
    See Also:
    
    Constant Field Values
  - DEFAULT_MAX_STRING_ENDING
```
protected static final String DEFAULT_MAX_STRING_ENDING
```
    Parameters kept in the details section are capped at a max length and this string is put at the end of the string after the truncation point to indicate there is more data that is not shown.
    
    See Also:
    
    Constant Field Values
  - MONITOR_PREFIX
```
protected static final String MONITOR_PREFIX
```
    See Also:
    
    Constant Field Values
  - exceptionLabel
```
protected String exceptionLabel
```
    JAMon exception label - can be overridden in subclasses. This name should represent a class of errors such as EJB errors as opposed to other types such as jdbc, or http errors. Example default value: com.jamonapi.aop.general.JAMonInterceptor
  - LINE_SEPARATOR
```
protected static final String LINE_SEPARATOR
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - JAMonInterceptor
```
protected JAMonInterceptor(String exceptionLabel)
```
  - JAMonInterceptor
```
public JAMonInterceptor()
```
- Method Detail
  - useParametersInDetails
```
public boolean useParametersInDetails()
```
  - setUseParametersInDetails
```
public JAMonInterceptor setUseParametersInDetails(boolean useParametersInDetails)
```
    Parameters:
    
    useParametersInDetails - Enable/disable saving parameter names and values in the 'detail' data section.
  - intercept
```
public Object intercept(javax.interceptor.InvocationContext ctx)
                 throws Exception
```
    Decorates method calls by monitoring them for performance and exceptions
    
    Parameters:
    
    ctx -
    
    Returns:
    
    Throws:
    
    Exception
  - getJamonLabel
```
protected String getJamonLabel(javax.interceptor.InvocationContext ctx)
```
    Returns JAMon's label for the specified Invocation context. By default it contains "method(args.length)"
    
    Parameters:
    
    ctx - Invocation context
    
    Returns:
    
    fully qualified label
  - isMonitored
```
protected boolean isMonitored(javax.interceptor.InvocationContext ctx)
```
    Indicates whether the method invocation should be monitored. Default behavior always returns true.
    
    Parameters:
    
    ctx - Method invocation context
    
    Returns:
    
    true to enable JAMon, false either
  - onException
```
protected String onException(javax.interceptor.InvocationContext ctx,
                             String label,
                             Exception exception)
                      throws Exception
```
    Default exception handling. This method creates a 'detail' string for viewing and creates three JAMon exception monitor to keep track of the exceptions - 1) one monitor is used as overall exception count, 2) another monitors tracks the EJB-related exceptions, 3) And a third tracks specific exception such as java.lang.RuntimeException. This method can be overridden.
    
    Parameters:
    
    ctx - Invocation context
    
    label - the label used for this method invocation
    
    exception - the offending exception
    
    Returns:
    
    Detailed string representing the exception. It has the method call, stacktrace and function parameter names and values (but anything can be returned that is useful context for debugging)
    
    Throws:
    
    Exception
  - createExceptionDetails
```
protected String createExceptionDetails(String label,
                                        Object[] parameters,
                                        Exception exception)
```
    Default exception handling. Creates the String used to display exception information in JAMon's "Exception Details" view. This logic creates a string representation of the stacktrace as well as all method parameter names and values.
    
    Parameters:
    
    label - the label used for this method invocation
    
    parameters - the method invocation parameters
    
    exception - the offending exception
    
    Returns:
    
    exception the offending exception thrown to the caller
  - toString
```
protected String toString(Object parameter)
```
    Turns a single method parameter into a string. To keep the functionality safe we truncate overly long strings and ignore any exceptions.

Class JAMonInterceptor

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EXCEPTION_UNITS

NULL_STR

UNKNOWN

DEFAULT_ARG_STRING_MAX_LENGTH

DEFAULT_MAX_STRING_ENDING

MONITOR_PREFIX

exceptionLabel

LINE_SEPARATOR

Constructor Detail

JAMonInterceptor

JAMonInterceptor

Method Detail

useParametersInDetails

setUseParametersInDetails

intercept

getJamonLabel

isMonitored

onException

createExceptionDetails

toString