er.extensions.foundation

Class ERXSimpleTemplateParser

java.lang.Object

er.extensions.foundation.ERXSimpleTemplateParser

public class ERXSimpleTemplateParser
extends Object

Very simple template parser. For example if you have the delimiter: @@, then a possible template might look like: "Hello, @@name@@. How are you feeling today?", In this case the object will get asked for the value name. This works with key-paths as well.

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_DELIMITER The default delimiter
static String	DEFAULT_UNDEFINED_KEY_LABEL The default label for keys not found while parsing
boolean	isLoggingDisabled Flag to disable logging.

Constructor Summary

Constructors

Constructor and Description
ERXSimpleTemplateParser() Returns a parser object with the default undefined label
ERXSimpleTemplateParser(String undefinedKeyLabel) Returns a parser object with the given string as the undefined key label

Method Summary

Modifier and Type	Method and Description
protected Object	doGetValue(String aKeyPath, Object anObject) To allow flexibility of the variable provider object type we use similar logic to NSDictionary valueForKeyPath.
NSArray	keysInTemplate(String template, String delimiter) Calculates the set of keys used in a given template for a given delimiter.
static String	parseTemplatedStringWithObject(String templateString, Object templateObject) Parses the given templateString with an ERXSimpleTemplateParser.
String	parseTemplateWithObject(String template, String delimiter, Object object) Cover method for calling the four argument method passing in null for the otherObject parameter.
String	parseTemplateWithObject(String template, String delimiter, Object object, Object otherObject) This method replaces the keys enclosed between the delimiter with the values found in object and otherObject.
static void	setSharedInstance(ERXSimpleTemplateParser newSharedInstance) Sets the shared instance of the template parser.
static ERXSimpleTemplateParser	sharedInstance() Convenience method to return the shared instance of the template parser.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_UNDEFINED_KEY_LABEL

public static final String DEFAULT_UNDEFINED_KEY_LABEL

The default label for keys not found while parsing

See Also:

Constant Field Values

DEFAULT_DELIMITER

public static final String DEFAULT_DELIMITER

The default delimiter

See Also:

Constant Field Values

isLoggingDisabled

public boolean isLoggingDisabled

Flag to disable logging. ERXPatternLayout will set this to true for its internal parser object in order to prevent an infinite debug logging loop.

Constructor Detail

ERXSimpleTemplateParser

public ERXSimpleTemplateParser()

Returns a parser object with the default undefined label

See Also:

DEFAULT_UNDEFINED_KEY_LABEL

ERXSimpleTemplateParser

public ERXSimpleTemplateParser(String undefinedKeyLabel)

Returns a parser object with the given string as the undefined key label

Parameters:

undefinedKeyLabel - string as the undefined key label, for example, "?", "N/A"

Method Detail

sharedInstance

public static ERXSimpleTemplateParser sharedInstance()

Convenience method to return the shared instance of the template parser.

Returns:

shared instance of the parser

See Also:

setSharedInstance(er.extensions.foundation.ERXSimpleTemplateParser)

setSharedInstance

public static void setSharedInstance(ERXSimpleTemplateParser newSharedInstance)

Sets the shared instance of the template parser.

Parameters:

newSharedInstance - the parser object that will be shared

See Also:

sharedInstance()

keysInTemplate

public NSArray keysInTemplate(String template,
                              String delimiter)

Calculates the set of keys used in a given template for a given delimiter.

Parameters:

template - to check for keys

delimiter - for finding keys

Returns:

array of keys

parseTemplateWithObject

public String parseTemplateWithObject(String template,
                                      String delimiter,
                                      Object object)

Cover method for calling the four argument method passing in null for the otherObject parameter. See that method for documentation.

Parameters:

template - to use to parse

delimiter - to use to find keys

object - to resolve keys

Returns:

parsed template with keys replaced

parseTemplateWithObject

public String parseTemplateWithObject(String template,
                                      String delimiter,
                                      Object object,
                                      Object otherObject)

This method replaces the keys enclosed between the delimiter with the values found in object and otherObject. It first looks for a value in object, and then in otherObject if the key is not found in object. Therefore, otherObject is a good place to store default values while object is a good place to override default values.

When the value is not found in both object and otherObject, it will replace the key with the undefined key label which defaults to "?". You can set the label via the constructor ERXSimpleTemplateParser(String). Note that a null result will also output the label, so you might want to have the empty string as the undefined key label.

Parameters:

template - to use to parse

delimiter - to use to check for keys

object - to resolve keys off of

otherObject - object used to resolve default keys

Returns:

parsed template with keys replaced

doGetValue

protected Object doGetValue(String aKeyPath,
                            Object anObject)

To allow flexibility of the variable provider object type we use similar logic to NSDictionary valueForKeyPath. Consequently java.util.Properties objects that use keyPath separator (.) in the property names (which is common) can be reliably used as object providers.

Parameters:

aKeyPath -

anObject -

Returns:

the value corresponding to either a key with value aKeypath, or when no key, a keyPath with value aKeyPath

parseTemplatedStringWithObject

public static String parseTemplatedStringWithObject(String templateString,
                                                    Object templateObject)

Parses the given templateString with an ERXSimpleTemplateParser.

Parameters:

templateString - the template string to parse

templateObject - the object to bind to

Returns:

the parsed template string