org.apache.commons.configuration.tree
Class DefaultConfigurationKey.KeyIterator

java.lang.Object
  extended by org.apache.commons.configuration.tree.DefaultConfigurationKey.KeyIterator
All Implemented Interfaces:
java.lang.Cloneable, java.util.Iterator
Enclosing class:
DefaultConfigurationKey

public class DefaultConfigurationKey.KeyIterator
extends java.lang.Object
implements java.util.Iterator, java.lang.Cloneable

A specialized iterator class for tokenizing a configuration key. This class implements the normal iterator interface. In addition it provides some specific methods for configuration keys.


Field Summary
private  boolean attribute
          Stores a flag if the actual property is an attribute.
private  java.lang.String current
          Stores the current key name.
private  int endIndex
          Stores the end index of the actual token.
private  boolean hasIndex
          Stores a flag if the actual property has an index.
private  int indexValue
          Stores the index of the actual property if there is one.
private  int startIndex
          Stores the start index of the actual token.
 
Constructor Summary
DefaultConfigurationKey.KeyIterator()
           
 
Method Summary
private  boolean checkAttribute(java.lang.String key)
          Helper method for checking if the passed key is an attribute.
private  boolean checkIndex(java.lang.String key)
          Helper method for checking if the passed key contains an index.
 java.lang.Object clone()
          Creates a clone of this object.
 java.lang.String currentKey()
          Returns the current key of the iteration (without skipping to the next element).
 java.lang.String currentKey(boolean decorated)
          Returns the current key of the iteration (without skipping to the next element).
private  int escapedPosition(java.lang.String key, int pos)
          Checks if a delimiter at the specified position is escaped.
private  int escapeOffset()
          Determines the relative offset of an escaped delimiter in relation to a delimiter.
private  java.lang.String findNextIndices()
          Helper method for determining the next indices.
 int getIndex()
          Returns the index value of the current key.
 boolean hasIndex()
          Returns a flag if the current key has an associated index.
 boolean hasNext()
          Checks if there is a next element.
 boolean isAttribute()
          Returns a flag if the current key is an attribute.
private  boolean isAttributeEmulatingMode()
          Returns a flag whether attributes are marked the same way as normal property keys.
 boolean isPropertyKey()
          Returns a flag whether the current key refers to a property (i.e.
 java.lang.Object next()
          Returns the next object in the iteration.
private  int nextDelimiterPos(java.lang.String key, int pos, int endPos)
          Searches the next unescaped delimiter from the given position.
 java.lang.String nextKey()
          Returns the next key part of this configuration key.
 java.lang.String nextKey(boolean decorated)
          Returns the next key part of this configuration key.
private  java.lang.String nextKeyPart()
          Helper method for extracting the next key part.
 void remove()
          Removes the current object in the iteration.
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

current

private java.lang.String current
Stores the current key name.


startIndex

private int startIndex
Stores the start index of the actual token.


endIndex

private int endIndex
Stores the end index of the actual token.


indexValue

private int indexValue
Stores the index of the actual property if there is one.


hasIndex

private boolean hasIndex
Stores a flag if the actual property has an index.


attribute

private boolean attribute
Stores a flag if the actual property is an attribute.

Constructor Detail

DefaultConfigurationKey.KeyIterator

public DefaultConfigurationKey.KeyIterator()
Method Detail

nextKey

public java.lang.String nextKey()
Returns the next key part of this configuration key. This is a short form of nextKey(false).

Returns:
the next key part

nextKey

public java.lang.String nextKey(boolean decorated)
Returns the next key part of this configuration key. The boolean parameter indicates wheter a decorated key should be returned. This affects only attribute keys: if the parameter is false, the attribute markers are stripped from the key; if it is true, they remain.

Parameters:
decorated - a flag if the decorated key is to be returned
Returns:
the next key part

hasNext

public boolean hasNext()
Checks if there is a next element.

Specified by:
hasNext in interface java.util.Iterator
Returns:
a flag if there is a next element

next

public java.lang.Object next()
Returns the next object in the iteration.

Specified by:
next in interface java.util.Iterator
Returns:
the next object

remove

public void remove()
Removes the current object in the iteration. This method is not supported by this iterator type, so an exception is thrown.

Specified by:
remove in interface java.util.Iterator

currentKey

public java.lang.String currentKey()
Returns the current key of the iteration (without skipping to the next element). This is the same key the previous next() call had returned. (Short form of currentKey(false).

Returns:
the current key

currentKey

public java.lang.String currentKey(boolean decorated)
Returns the current key of the iteration (without skipping to the next element). The boolean parameter indicates wheter a decorated key should be returned. This affects only attribute keys: if the parameter is false, the attribute markers are stripped from the key; if it is true, they remain.

Parameters:
decorated - a flag if the decorated key is to be returned
Returns:
the current key

isAttribute

public boolean isAttribute()
Returns a flag if the current key is an attribute. This method can be called after next().

Returns:
a flag if the current key is an attribute

isPropertyKey

public boolean isPropertyKey()
Returns a flag whether the current key refers to a property (i.e. is no special attribute key). Usually this method will return the opposite of isAttribute(), but if the delimiters for normal properties and attributes are set to the same string, it is possible that both methods return true.

Returns:
a flag if the current key is a property key
See Also:
isAttribute()

getIndex

public int getIndex()
Returns the index value of the current key. If the current key does not have an index, return value is -1. This method can be called after next().

Returns:
the index value of the current key

hasIndex

public boolean hasIndex()
Returns a flag if the current key has an associated index. This method can be called after next().

Returns:
a flag if the current key has an index

clone

public java.lang.Object clone()
Creates a clone of this object.

Overrides:
clone in class java.lang.Object
Returns:
a clone of this object

findNextIndices

private java.lang.String findNextIndices()
Helper method for determining the next indices.

Returns:
the next key part

nextKeyPart

private java.lang.String nextKeyPart()
Helper method for extracting the next key part. Takes escaping of delimiter characters into account.

Returns:
the next key part

nextDelimiterPos

private int nextDelimiterPos(java.lang.String key,
                             int pos,
                             int endPos)
Searches the next unescaped delimiter from the given position.

Parameters:
key - the key
pos - the start position
endPos - the end position
Returns:
the position of the next delimiter or -1 if there is none

escapedPosition

private int escapedPosition(java.lang.String key,
                            int pos)
Checks if a delimiter at the specified position is escaped. If this is the case, the next valid search position will be returned. Otherwise the return value is -1.

Parameters:
key - the key to check
pos - the position where a delimiter was found
Returns:
information about escaped delimiters

escapeOffset

private int escapeOffset()
Determines the relative offset of an escaped delimiter in relation to a delimiter. Depending on the used delimiter and escaped delimiter tokens the position where to search for an escaped delimiter is different. If, for instance, the dot character (".") is used as delimiter, and a doubled dot ("..") as escaped delimiter, the escaped delimiter starts at the same position as the delimiter. If the token "\." was used, it would start one character before the delimiter because the delimiter character "." is the second character in the escaped delimiter string. This relation will be determined by this method. For this to work the delimiter string must be contained in the escaped delimiter string.

Returns:
the relative offset of the escaped delimiter in relation to a delimiter

checkAttribute

private boolean checkAttribute(java.lang.String key)
Helper method for checking if the passed key is an attribute. If this is the case, the internal fields will be set.

Parameters:
key - the key to be checked
Returns:
a flag if the key is an attribute

checkIndex

private boolean checkIndex(java.lang.String key)
Helper method for checking if the passed key contains an index. If this is the case, internal fields will be set.

Parameters:
key - the key to be checked
Returns:
a flag if an index is defined

isAttributeEmulatingMode

private boolean isAttributeEmulatingMode()
Returns a flag whether attributes are marked the same way as normal property keys. We call this the "attribute emulating mode". When navigating through node hierarchies it might be convenient to treat attributes the same way than other child nodes, so an expression engine supports to set the attribute markers to the same value than the property delimiter. If this is the case, some special checks have to be performed.

Returns:
a flag if attributes and normal property keys are treated the same way