org.apache.wiki
Class VariableManager

java.lang.Object
  org.apache.wiki.VariableManager

public class VariableManager
extends Object

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

static String	VAR_ERROR
static String	VAR_MSG

Constructor Summary

VariableManager(Properties props)
Creates a VariableManager object using the property list given.

Method Summary

String	expandVariables(WikiContext context, String source) This method does in-place expansion of any variables.
String	getValue(WikiContext context, String varName) Returns a value of the named variable.
String	getValue(WikiContext context, String varName, String defValue) Returns the value of a named variable.
static boolean	isVariableLink(String link) Returns true if the link is really command to insert a variable.
String	parseAndGetValue(WikiContext context, 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

Field Detail

VAR_ERROR

public static final String VAR_ERROR

See Also:

Constant Field Values

VAR_MSG

public static final String VAR_MSG

See Also:

Constant Field Values

Constructor Detail

VariableManager

public VariableManager(Properties props)

Creates a VariableManager object using the property list given.

Parameters:

props - The properties.

Method Detail

isVariableLink

public static boolean isVariableLink(String link)

Returns true if the link is really command to insert a variable.

Currently we just check if the link starts with "{$".

Parameters:

link - The link text

Returns:

true, if this represents a variable link.

parseAndGetValue

public String parseAndGetValue(WikiContext context,
                               String link)
                        throws IllegalArgumentException,
                               NoSuchVariableException

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

Parameters:

context - The WikiContext

link - The link text containing the variable name.

Returns:

The variable value.

Throws:

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

NoSuchVariableException - If a variable is not known.

expandVariables

public String expandVariables(WikiContext context,
                              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.

Parameters:

context - The WikiContext of the current page.

source - The source string.

Returns:

The source string with variables expanded.

getValue

public String getValue(WikiContext context,
                       String varName,
                       String defValue)

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

Parameters:

context - WikiContext

varName - The name of the variable

defValue - A default value.

Returns:

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

getValue

public String getValue(WikiContext context,
                       String varName)
                throws 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.

Parameters:

context - The WikiContext

varName - Name of the variable.

Returns:

The variable value.

Throws:

IllegalArgumentException - If the name is somehow broken.

NoSuchVariableException - If a variable is not known.