Package chapters.onJoran.calculator
Class ComputationAction2
- java.lang.Object
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- ch.qos.logback.core.spi.ContextAwareBase
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- ch.qos.logback.core.joran.action.Action
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- chapters.onJoran.calculator.ComputationAction2
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- All Implemented Interfaces:
ContextAware
public class ComputationAction2 extends Action
ComputationAction2 will print the result of the compuration made by children elements but only if the computation itself is named, that is if the name attribute of the associated computation element is not null. In other words, anonymous computations will not print their result. ComputationAction2 differs from ComputationAction1 in its handling of instance variables. ComputationAction1 has a simplenameStr
instance variable. This variable is set when the begin() method is called and then later used within the end() method. This simple approach works properly if the begin() and end() method of a given action are expected to be called in sequence. However, there are situations where the begin() method of the same action instance is invoked multiple times before the matching end() method is invoked. When this happens, the second call to begin() overwrites values set by the first invocation to begin(). The solution is to save parameter values into a separate stack. The well-formedness of XML will guarantee that a value saved by one begin() will be consumed only by the matching end() method. Note that in the vast majority of cases there is no need to resort to a separate stack for each variable. The situation of successive begin() invocations can only occur if: 1) the associated pattern contains a wildcard, i.e. the * character and 2) the associated element tag can contain itself as a child For example, "*/computation" pattern means that computations can contain other computation elements as children.
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Field Summary
Fields Modifier and Type Field Description static java.lang.String
NAME_ATR
(package private) java.util.Stack<java.lang.String>
nameStrStack
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Fields inherited from class ch.qos.logback.core.joran.action.Action
ACTION_CLASS_ATTRIBUTE, CLASS_ATTRIBUTE, FILE_ATTRIBUTE, KEY_ATTRIBUTE, NAME_ATTRIBUTE, PATTERN_ATTRIBUTE, SCOPE_ATTRIBUTE, VALUE_ATTRIBUTE
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Fields inherited from class ch.qos.logback.core.spi.ContextAwareBase
context
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Constructor Summary
Constructors Constructor Description ComputationAction2()
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
begin(InterpretationContext ec, java.lang.String name, org.xml.sax.Attributes attributes)
Called when the parser encounters an element matching aPattern
.void
end(InterpretationContext ec, java.lang.String name)
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Methods inherited from class ch.qos.logback.core.joran.action.Action
body, getColumnNumber, getLineColStr, getLineNumber, toString
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Methods inherited from class ch.qos.logback.core.spi.ContextAwareBase
addError, addError, addInfo, addInfo, addStatus, addWarn, addWarn, getContext, getDeclaredOrigin, getStatusManager, setContext
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Field Detail
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NAME_ATR
public static final java.lang.String NAME_ATR
- See Also:
- Constant Field Values
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nameStrStack
java.util.Stack<java.lang.String> nameStrStack
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Method Detail
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begin
public void begin(InterpretationContext ec, java.lang.String name, org.xml.sax.Attributes attributes)
Description copied from class:Action
Called when the parser encounters an element matching aPattern
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end
public void end(InterpretationContext ec, java.lang.String name)
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