org.apache.wiki.variables

Class DefaultVariableManager

java.lang.Object

org.apache.wiki.variables.DefaultVariableManager

All Implemented Interfaces:

VariableManager

public class DefaultVariableManager
extends java.lang.Object
implements VariableManager

Manages variables. Variables are case-insensitive. A list of all available variables is on a Wiki page called "WikiVariables".

Since:

1.9.20.

Field Summary

Fields inherited from interface org.apache.wiki.variables.VariableManager

VAR_ERROR, VAR_MSG, VAR_RUNFILTERS

Constructor Summary

Constructors

Constructor and Description
DefaultVariableManager(java.util.Properties props) Creates a VariableManager object using the property list given.

Method Summary

Modifier and Type	Method and Description
java.lang.String	expandVariables(Context context, java.lang.String source) This method does in-place expansion of any variables.
java.lang.String	getValue(Context context, java.lang.String varName) Returns a value of the named variable.
java.lang.String	getValue(Context context, java.lang.String varName, java.lang.String defValue) Returns the value of a named variable.
java.lang.String	getVariable(Context context, java.lang.String name) Shortcut to getValue().
java.lang.String	parseAndGetValue(Context context, java.lang.String link) Parses the link and finds a value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DefaultVariableManager

public DefaultVariableManager(java.util.Properties props)

Creates a VariableManager object using the property list given.

Parameters:

props - The properties.

Method Detail

parseAndGetValue

public java.lang.String parseAndGetValue(Context context,
                                         java.lang.String link)
                                  throws java.lang.IllegalArgumentException,
                                         NoSuchVariableException

Parses the link and finds a value. This is essentially used once LinkParsingOperations#isVariableLink(String) has found that the link text actually contains a variable. For example, you could pass in "{$username}" and get back "JanneJalkanen".

Specified by:

parseAndGetValue in interface VariableManager

Parameters:

context - The WikiContext

link - The link text containing the variable name.

Returns:

The variable value.

Throws:

java.lang.IllegalArgumentException - If the format is not valid (does not start with "{$", is zero length, etc.)

NoSuchVariableException - If a variable is not known.

expandVariables

public java.lang.String expandVariables(Context context,
                                        java.lang.String source)

This method does in-place expansion of any variables. However, the expansion is not done twice, that is, a variable containing text $variable will not be expanded.

The variables should be in the same format ({$variablename} as in the web pages.

Specified by:

expandVariables in interface VariableManager

Parameters:

context - The WikiContext of the current page.

source - The source string.

Returns:

The source string with variables expanded.

getValue

public java.lang.String getValue(Context context,
                                 java.lang.String varName,
                                 java.lang.String defValue)

Returns the value of a named variable. See VariableManager.getValue(Context, String). The only difference is that this method does not throw an exception, but it returns the given default value instead.

Specified by:

getValue in interface VariableManager

Parameters:

context - WikiContext

varName - The name of the variable

defValue - A default value.

Returns:

The variable value, or if not found, the default value.

getVariable

public java.lang.String getVariable(Context context,
                                    java.lang.String name)

Shortcut to getValue(). However, this method does not throw a NoSuchVariableException, but returns null in case the variable does not exist.

Specified by:

getVariable in interface VariableManager

Parameters:

context - WikiContext to look the variable in

name - Name of the variable to look for

Returns:

Variable value, or null, if there is no such variable.

getValue

public java.lang.String getValue(Context context,
                                 java.lang.String varName)
                          throws java.lang.IllegalArgumentException,
                                 NoSuchVariableException

Returns a value of the named variable. The resolving order is

1. Known "constant" name, such as "pagename", etc. This is so that pages could not override certain constants.
2. WikiContext local variable. This allows a programmer to set a parameter which cannot be overridden by user.
3. HTTP Session
4. HTTP Request parameters
5. WikiPage variable. As set by the user with the SET directive.
6. jspwiki.properties

Use this method only whenever you really need to have a parameter that can be overridden by anyone using the wiki.

Specified by:

getValue in interface VariableManager

Parameters:

context - The WikiContext

varName - Name of the variable.

Returns:

The variable value.

Throws:

java.lang.IllegalArgumentException - If the name is somehow broken.

NoSuchVariableException - If a variable is not known.