CallMethodRule (Apache Tomcat 7.0.109 API Documentation)

java.lang.Object
- org.apache.tomcat.util.digester.Rule
- - org.apache.tomcat.util.digester.CallMethodRule

```
public class CallMethodRule
extends Rule
```
Rule implementation that calls a method on an object on the stack (normally the top/parent object), passing arguments collected from subsequent CallParamRule rules or from the body of this element.

By using CallMethodRule(String methodName) a method call can be made to a method which accepts no arguments.

Incompatible method parameter types are converted using org.apache.commons.beanutils.ConvertUtils.

This rule now uses org.apache.commons.beanutils.MethodUtils#invokeMethod by default. This increases the kinds of methods successfully and allows primitives to be matched by passing in wrapper classes. There are rare cases when org.apache.commons.beanutils.MethodUtils#invokeExactMethod (the old default) is required. This method is much stricter in its reflection. Setting the UseExactMatch to true reverts to the use of this method.

Note that the target method is invoked when the end of the tag the CallMethodRule fired on is encountered, not when the last parameter becomes available. This implies that rules which fire on tags nested within the one associated with the CallMethodRule will fire before the CallMethodRule invokes the target method. This behaviour is not configurable.

Note also that if a CallMethodRule is expecting exactly one parameter and that parameter is not available (eg CallParamRule is used with an attribute name but the attribute does not exist) then the method will not be invoked. If a CallMethodRule is expecting more than one parameter, then it is always invoked, regardless of whether the parameters were available or not (missing parameters are passed as null values).

Field Summary

Fields
Modifier and Type	Field and Description
`protected String`	`bodyText` The body text collected from this element.
`protected String`	`methodName` The method name to call on the parent object.
`protected String[]`	`paramClassNames` The names of the classes of the parameters to be collected.
`protected int`	`paramCount` The number of parameters to collect from `MethodParam` rules.
`protected Class<?>[]`	`paramTypes` The parameter types of the parameters to be collected.
`protected int`	`targetOffset` location of the target object for the call, relative to the top of the digester object stack.
`protected boolean`	`useExactMatch` Should `MethodUtils.invokeExactMethod` be used for reflection.

Fields inherited from class org.apache.tomcat.util.digester.Rule
digester, namespaceURI

Constructor Summary

Constructors
Constructor and Description
`CallMethodRule(int targetOffset, String methodName)` Construct a "call method" rule with the specified method name.
`CallMethodRule(int targetOffset, String methodName, int paramCount)` Construct a "call method" rule with the specified method name.
`CallMethodRule(int targetOffset, String methodName, int paramCount, Class<?>[] paramTypes)` Construct a "call method" rule with the specified method name and parameter types.
`CallMethodRule(int targetOffset, String methodName, int paramCount, String[] paramTypes)` Construct a "call method" rule with the specified method name and parameter types.
`CallMethodRule(String methodName)` Construct a "call method" rule with the specified method name.
`CallMethodRule(String methodName, int paramCount)` Construct a "call method" rule with the specified method name.
`CallMethodRule(String methodName, int paramCount, Class<?>[] paramTypes)` Construct a "call method" rule with the specified method name and parameter types.
`CallMethodRule(String methodName, int paramCount, String[] paramTypes)` Construct a "call method" rule with the specified method name and parameter types.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`begin(String namespace, String name, Attributes attributes)` Process the start of this element.
`void`	`body(String namespace, String name, String bodyText)` Process the body text of this element.
`void`	`end(String namespace, String name)` Process the end of this element.
`void`	`finish()` Clean up after parsing is complete.
`boolean`	`getUseExactMatch()` Should `MethodUtils.invokeExactMethod` be used for the reflection.
`protected void`	`processMethodCallResult(Object result)` Subclasses may override this method to perform additional processing of the invoked method's result.
`void`	`setDigester(Digester digester)` Set the associated digester.
`void`	`setUseExactMatch(boolean useExactMatch)` Set whether `MethodUtils.invokeExactMethod` should be used for the reflection.
`String`	`toString()` Render a printable version of this Rule.

Methods inherited from class org.apache.tomcat.util.digester.Rule
begin, body, end, getDigester, getNamespaceURI, setNamespaceURI

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

- Field Detail
  - bodyText
```
protected String bodyText
```
    The body text collected from this element.
  - targetOffset
```
protected int targetOffset
```
    location of the target object for the call, relative to the top of the digester object stack. The default value of zero means the target object is the one on top of the stack.
  - methodName
```
protected String methodName
```
    The method name to call on the parent object.
  - paramCount
```
protected int paramCount
```
    The number of parameters to collect from MethodParam rules. If this value is zero, a single parameter will be collected from the body of this element.
  - paramTypes
```
protected Class<?>[] paramTypes
```
    The parameter types of the parameters to be collected.
  - paramClassNames
```
protected String[] paramClassNames
```
    The names of the classes of the parameters to be collected. This attribute allows creation of the classes to be postponed until the digester is set.
  - useExactMatch
```
protected boolean useExactMatch
```
    Should MethodUtils.invokeExactMethod be used for reflection.
- Constructor Detail
  - CallMethodRule
```
public CallMethodRule(String methodName,
              int paramCount)
```
    Construct a "call method" rule with the specified method name. The parameter types (if any) default to java.lang.String.
    
    Parameters:
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element.
  - CallMethodRule
```
public CallMethodRule(int targetOffset,
              String methodName,
              int paramCount)
```
    Construct a "call method" rule with the specified method name. The parameter types (if any) default to java.lang.String.
    
    Parameters:
    targetOffset - location of the target object. Positive numbers are relative to the top of the digester object stack. Negative numbers are relative to the bottom of the stack. Zero implies the top object on the stack.
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element.
  - CallMethodRule
```
public CallMethodRule(String methodName)
```
    Construct a "call method" rule with the specified method name. The method should accept no parameters.
    
    Parameters:
    methodName - Method name of the parent method to call
  - CallMethodRule
```
public CallMethodRule(int targetOffset,
              String methodName)
```
    Construct a "call method" rule with the specified method name. The method should accept no parameters.
    
    Parameters:
    targetOffset - location of the target object. Positive numbers are relative to the top of the digester object stack. Negative numbers are relative to the bottom of the stack. Zero implies the top object on the stack.
    methodName - Method name of the parent method to call
  - CallMethodRule
```
public CallMethodRule(String methodName,
              int paramCount,
              String[] paramTypes)
```
    Construct a "call method" rule with the specified method name and parameter types. If paramCount is set to zero the rule will use the body of this element as the single argument of the method, unless paramTypes is null or empty, in this case the rule will call the specified method with no arguments.
    
    Parameters:
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element
    paramTypes - The Java class names of the arguments (if you wish to use a primitive type, specify the corresponding Java wrapper class instead, such as java.lang.Boolean for a boolean parameter)
  - CallMethodRule
```
public CallMethodRule(int targetOffset,
              String methodName,
              int paramCount,
              String[] paramTypes)
```
    Construct a "call method" rule with the specified method name and parameter types. If paramCount is set to zero the rule will use the body of this element as the single argument of the method, unless paramTypes is null or empty, in this case the rule will call the specified method with no arguments.
    
    Parameters:
    targetOffset - location of the target object. Positive numbers are relative to the top of the digester object stack. Negative numbers are relative to the bottom of the stack. Zero implies the top object on the stack.
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element
    paramTypes - The Java class names of the arguments (if you wish to use a primitive type, specify the corresponding Java wrapper class instead, such as java.lang.Boolean for a boolean parameter)
  - CallMethodRule
```
public CallMethodRule(String methodName,
              int paramCount,
              Class<?>[] paramTypes)
```
    Construct a "call method" rule with the specified method name and parameter types. If paramCount is set to zero the rule will use the body of this element as the single argument of the method, unless paramTypes is null or empty, in this case the rule will call the specified method with no arguments.
    
    Parameters:
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element
    paramTypes - The Java classes that represent the parameter types of the method arguments (if you wish to use a primitive type, specify the corresponding Java wrapper class instead, such as java.lang.Boolean.TYPE for a boolean parameter)
  - CallMethodRule
```
public CallMethodRule(int targetOffset,
              String methodName,
              int paramCount,
              Class<?>[] paramTypes)
```
    Construct a "call method" rule with the specified method name and parameter types. If paramCount is set to zero the rule will use the body of this element as the single argument of the method, unless paramTypes is null or empty, in this case the rule will call the specified method with no arguments.
    
    Parameters:
    targetOffset - location of the target object. Positive numbers are relative to the top of the digester object stack. Negative numbers are relative to the bottom of the stack. Zero implies the top object on the stack.
    methodName - Method name of the parent method to call
    paramCount - The number of parameters to collect, or zero for a single argument from the body of this element
    paramTypes - The Java classes that represent the parameter types of the method arguments (if you wish to use a primitive type, specify the corresponding Java wrapper class instead, such as java.lang.Boolean.TYPE for a boolean parameter)
- Method Detail
  - getUseExactMatch
```
public boolean getUseExactMatch()
```
    Should MethodUtils.invokeExactMethod be used for the reflection.
  - setUseExactMatch
```
public void setUseExactMatch(boolean useExactMatch)
```
    Set whether MethodUtils.invokeExactMethod should be used for the reflection.
  - setDigester
```
public void setDigester(Digester digester)
```
    Set the associated digester. If needed, this class loads the parameter classes from their names.
    
    Overrides:
    
    setDigester in class Rule
  - begin
```
public void begin(String namespace,
         String name,
         Attributes attributes)
           throws Exception
```
    Process the start of this element.
    
    Overrides:
    
    begin in class Rule
    
    Parameters:
    namespace - the namespace URI of the matching element, or an empty string if the parser is not namespace aware or the element has no namespace
    name - the local name if the parser is namespace aware, or just the element name otherwise
    attributes - The attribute list for this element
    
    Throws:
    
    Exception
  - body
```
public void body(String namespace,
        String name,
        String bodyText)
          throws Exception
```
    Process the body text of this element.
    
    Overrides:
    
    body in class Rule
    
    Parameters:
    namespace - the namespace URI of the matching element, or an empty string if the parser is not namespace aware or the element has no namespace
    name - the local name if the parser is namespace aware, or just the element name otherwise
    bodyText - The body text of this element
    
    Throws:
    
    Exception
  - end
```
public void end(String namespace,
       String name)
         throws Exception
```
    Process the end of this element.
    
    Overrides:
    
    end in class Rule
    
    Parameters:
    namespace - the namespace URI of the matching element, or an empty string if the parser is not namespace aware or the element has no namespace
    name - the local name if the parser is namespace aware, or just the element name otherwise
    
    Throws:
    
    Exception
  - finish
```
public void finish()
            throws Exception
```
    Clean up after parsing is complete.
    
    Overrides:
    
    finish in class Rule
    
    Throws:
    
    Exception
  - processMethodCallResult
```
protected void processMethodCallResult(Object result)
```
    Subclasses may override this method to perform additional processing of the invoked method's result.
    
    Parameters:
    result - the Object returned by the method invoked, possibly null
  - toString
```
public String toString()
```
    Render a printable version of this Rule.
    
    Overrides:
    
    toString in class Object

Class CallMethodRule

Field Summary

Fields inherited from class org.apache.tomcat.util.digester.Rule

Constructor Summary

Method Summary

Methods inherited from class org.apache.tomcat.util.digester.Rule

Methods inherited from class java.lang.Object

Field Detail

bodyText

targetOffset

methodName

paramCount

paramTypes

paramClassNames

useExactMatch

Constructor Detail

CallMethodRule

CallMethodRule

CallMethodRule

CallMethodRule

CallMethodRule

CallMethodRule

CallMethodRule

CallMethodRule

Method Detail

getUseExactMatch

setUseExactMatch

setDigester

begin

body

end

finish

processMethodCallResult

toString