TracingInterceptor (Groovy 6.0.0-alpha-1)

groovy.lang.TracingInterceptor

All Implemented Interfaces and Traits:: Interceptor

public class TracingInterceptor
extends Object
implements Interceptor

This Interceptor traces method calls on the proxied object to a log. By default, the log is simply

System.out

; however, that can be changed with the

setWriter(Writer)

method.

A message will be written to output before a method is invoked and after a method is invoked. If methods are nested, and invoke one another, then indentation of two spaces is written.

Here is an example usage on the ArrayList object:


 def proxy = ProxyMetaClass.getInstance(ArrayList.class)
 proxy.interceptor = new TracingInterceptor()
 proxy.use {
     def list = [1, 2, 3]
     assert 3 == list.size()
     assert list.contains(1)
 }

Running this code produces this output:


 before java.util.ArrayList.size()
 after  java.util.ArrayList.size()
 before java.util.ArrayList.contains(java.lang.Integer)
 after  java.util.ArrayList.contains(java.lang.Integer)

Field Summary

Fields
Modifiers	Name	Description
`protected Writer`	`writer`	Writer used to emit trace output.

Methods Summary

Methods
Type Params	Return Type	Name and description
	`public Object`	`afterInvoke(Object object, String methodName, Object[] arguments, Object result)` This code is executed after the method is optionally called. Parameters: `object` - receiver object for the called method `methodName` - name of the called method `arguments` - arguments to the called method `result` - result of the executed method call or result of beforeInvoke if method was not called Returns: any arbitrary result that can replace the result of the original method call. Typically, the result parameter is returned.
	`public Object`	`beforeInvoke(Object object, String methodName, Object[] arguments)` This code is executed before the method is optionally called. Parameters: `object` - receiver object for the method call `methodName` - name of the method to call `arguments` - arguments to the method call Returns: any arbitrary result that replaces the result of the original method call only if doInvoke() returns false and afterInvoke() relays this result.
	`public boolean`	`doInvoke()` Returns: whether the target method should be invoked at all.
	`public Writer`	`getWriter()` Returns the writer associated with this interceptor.
	`public void`	`setWriter(Writer writer)` Changes the writer associated with this interceptor.
	`protected void`	`write(Object object, String methodName, Object[] arguments, String origin)` Writes a formatted trace line for the supplied invocation stage.
	`protected void`	`writeInfo(Class aClass, String methodName, Object[] arguments)` Writes a trace line describing the intercepted method invocation.

Inherited Methods Summary

Inherited Methods
Methods inherited from class	Name
`class Object`	`equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- Field Detail
  - protected Writer writer
    
    Writer used to emit trace output.
- Method Detail
  - public Object afterInvoke(Object object, String methodName, Object[] arguments, Object result)
    
    This code is executed after the method is optionally called.
    Parameters:
    object - receiver object for the called method
    methodName - name of the called method
    arguments - arguments to the called method
    result - result of the executed method call or result of beforeInvoke if method was not called
    Returns:
    any arbitrary result that can replace the result of the original method call. Typically, the result parameter is returned.
  - public Object beforeInvoke(Object object, String methodName, Object[] arguments)
    
    This code is executed before the method is optionally called.
    Parameters:
    object - receiver object for the method call
    methodName - name of the method to call
    arguments - arguments to the method call
    Returns:
    any arbitrary result that replaces the result of the original method call only if doInvoke() returns false and afterInvoke() relays this result.
  - public boolean doInvoke()
    
    Returns:
    whether the target method should be invoked at all.
  - public Writer getWriter()
    
    Returns the writer associated with this interceptor.
  - public void setWriter(Writer writer)
    
    Changes the writer associated with this interceptor.
  - protected void write(Object object, String methodName, Object[] arguments, String origin)
    
    Writes a formatted trace line for the supplied invocation stage.
    Parameters:
    object - the receiver object
    methodName - the invoked method name
    arguments - the invocation arguments
    origin - the trace prefix to write
  - protected void writeInfo(Class aClass, String methodName, Object[] arguments)
    
    Writes a trace line describing the intercepted method invocation.
    throws:
    IOException if the trace output cannot be written
    
    Parameters:
    aClass - the declaring or receiver class to report
    methodName - the intercepted method name
    arguments - the intercepted arguments

Summary:
Field
Method

| Detail:
Field
Method

[Java] Class TracingInterceptor

Field Summary

Methods Summary

Inherited Methods Summary

Field Detail

protected Writer writer

Method Detail

public Object afterInvoke(Object object, String methodName, Object[] arguments, Object result)

public Object beforeInvoke(Object object, String methodName, Object[] arguments)

public boolean doInvoke()

public Writer getWriter()

public void setWriter(Writer writer)

protected void write(Object object, String methodName, Object[] arguments, String origin)

protected void writeInfo(Class aClass, String methodName, Object[] arguments)