com.bea.p13n.content.expression
Class ExpressionHelper

java.lang.Object
  com.bea.p13n.content.expression.ExpressionHelper

public class ExpressionHelper

extends Object

Helper class to handle dealing with content Expressions.

For details on what content expression should look like, see parse(java.lang.String).

Nested Class Summary

static class

ExpressionHelper.ParseException Deprecated. Exception to report an error while parsing a query expression.

Field Summary

static String	AND Deprecated. Syntax textual and logical operator.
static String	CONTAINS Deprecated. Syntax textual contains operator.
static String	CONTAINS_ALL Deprecated. Syntax textual contains all operator.
static String	defDateFormatStr Deprecated. The default datetime format string in the content expression syntax ("MM/dd/yyyy HH:mm:ss z").
static String	EQUALS Deprecated. Syntax textual equals operator.
static String	GREATER_THAN Deprecated. Syntax textual greater than operator.
static String	GREATER_THAN_EQUALS Deprecated. Syntax textual greater than or equals operator.
static String	LESS_THAN Deprecated. Syntax textual less than operator.
static String	LESS_THAN_EQUALS Deprecated. Syntax textual less than or equals operator.
static String	LIKE Deprecated. Syntax textual like operator.
static String	LIKE_IGNORECASE Deprecated. Syntax textual case-insensitive like operator.
static String	NOT_EQUALS Deprecated. Syntax textual not equals operator.
static String	OR Deprecated. Syntax textual or logical operator.

Constructor Summary

ExpressionHelper()
Deprecated.

Method Summary

static ExpressionHelper.ParseException	convertException(Exception excep) Deprecated. Convert a generic exception into a ParseException.
static String	fromStringLiteral(String in) Deprecated. Convert a String literal (which may contain quoted characters) into a corresponding String value.
static String	getComparator(Expression expr) Deprecated. Get the syntax comparator textual operator for the given leaf node.
static String	getContentId(Expression expr) Deprecated. Return the content id from the expression, if it's an expression for a single content object based upon identifier.
static Search	getContentIdSearch(String contentId) Deprecated. Get a search object for a single content based upon the supplied id.
static Search	getContentNameSearch(String name) Deprecated. Get a search object for a single content based upon the name/path.
static PropertyRef	getLeftHandSide(Expression expr) Deprecated. Get the left-hand-side of a valid leaf node, which should be a PropertyRef
static String	getLogicalComparator(Expression expr) Deprecated. Get the syntax logical comparator textual operator for the given branch node.
static int	getOrdinalValue(char ch) Deprecated. Get the ordinal (Unicode) value of a character.
static Object	getRightHandSide(Expression expr) Deprecated. Get the right-hand-side of a valid leaf node.
static Expression	getSubExpression(Expression expr, int count) Deprecated.
static boolean	isHexString(String str) Deprecated. Determine if a string contains only ASCII hexidecimal characters ([0-9a-fA-F]).
static Expression	isLogicalNot(Expression expr) Deprecated. Tell if an expression is really a logical not and, if so, returned the contained expression.
static boolean	isValidBranchNode(Expression expr) Deprecated. Tell if an expression is a valid content branch node type.
static boolean	isValidLeafNode(Expression expr) Deprecated. Tell if an expression is a valid content leaf node type.
static LogicalAnd	join(Expression expr1, Expression expr2) Deprecated. Join together two expression via an AND expression.
static Expression	normalize(Expression expr) Deprecated. Normalize an Expression.
static Expression	parse(String queryStr) Deprecated. Convert a query expression string into an Expression object.
static void	print(PrintWriter out, Expression expr) Deprecated. Print a string representation of the given expression.
static void	printBranchNode(PrintWriter out, Expression expr) Deprecated. Return a string representation of the given expression branch.
static void	printLeafNode(PrintWriter out, Expression expr) Deprecated. Return a string representation of the given leaf expression node.
static void	printTree(int depth, PrintWriter out, Expression expr) Deprecated. For debug purposes, print the given expression as a tree at the given depth.
static void	printTree(PrintWriter out, Expression expr) Deprecated. For debug purposes, print the given expression as a tree.
static Expression	realize(Expression expr, PropertyProvider props) Deprecated. Realize an expression, which can contain property references, into an an expression which contains only literal values and can be sent to a ContentManager.
static String	toString(Expression expr) Deprecated. Get a string representation of the given expression.
static String	toStringLiteral(String in) Deprecated. Get an ASCII String literal from a Java string.
static String	toTree(Expression expr) Deprecated. For debug purposes, return a tree representation of the given expression.

Methods inherited from class java.lang.Object

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

Field Detail

AND

public static final String AND

Deprecated.

Syntax textual and logical operator.

See Also:

Constant Field Values

CONTAINS

public static final String CONTAINS

Deprecated.

Syntax textual contains operator.

See Also:

Constant Field Values

CONTAINS_ALL

public static final String CONTAINS_ALL

Deprecated.

Syntax textual contains all operator.

See Also:

Constant Field Values

defDateFormatStr

public static final String defDateFormatStr

Deprecated.

The default datetime format string in the content expression syntax ("MM/dd/yyyy HH:mm:ss z").

See Also:

Constant Field Values

EQUALS

public static final String EQUALS

Deprecated.

Syntax textual equals operator.

See Also:

Constant Field Values

GREATER_THAN

public static final String GREATER_THAN

Deprecated.

Syntax textual greater than operator.

See Also:

Constant Field Values

GREATER_THAN_EQUALS

public static final String GREATER_THAN_EQUALS

Deprecated.

Syntax textual greater than or equals operator.

See Also:

Constant Field Values

LESS_THAN

public static final String LESS_THAN

Deprecated.

Syntax textual less than operator.

See Also:

Constant Field Values

LESS_THAN_EQUALS

public static final String LESS_THAN_EQUALS

Deprecated.

Syntax textual less than or equals operator.

See Also:

Constant Field Values

LIKE

public static final String LIKE

Deprecated.

Syntax textual like operator.

See Also:

Constant Field Values

LIKE_IGNORECASE

public static final String LIKE_IGNORECASE

Deprecated.

Syntax textual case-insensitive like operator.

See Also:

Constant Field Values

NOT_EQUALS

public static final String NOT_EQUALS

Deprecated.

Syntax textual not equals operator.

See Also:

Constant Field Values

OR

public static final String OR

Deprecated.

Syntax textual or logical operator.

See Also:

Constant Field Values

Constructor Detail

ExpressionHelper

public ExpressionHelper()

Deprecated.

Method Detail

convertException

public static ExpressionHelper.ParseException convertException(Exception excep)

Deprecated.

Convert a generic exception into a ParseException.

fromStringLiteral

public static String fromStringLiteral(String in)

Deprecated.

Convert a String literal (which may contain quoted characters) into a corresponding String value.

This supports the standard Java Language Specification escape sequences.

Parameters:

in - the input string literal.

Returns:

the string value.

getComparator

public static String getComparator(Expression expr)
                            throws IllegalArgumentException

Deprecated.

Get the syntax comparator textual operator for the given leaf node.

Throws:

IllegalArgumentException

getContentId

public static String getContentId(Expression expr)

Deprecated.

Return the content id from the expression, if it's an expression for a single content object based upon identifier.

Returns:

the content id, or null if it's not a identifier equality expression.

getContentIdSearch

public static Search getContentIdSearch(String contentId)

Deprecated.

Get a search object for a single content based upon the supplied id.

getContentNameSearch

public static Search getContentNameSearch(String name)

Deprecated.

Get a search object for a single content based upon the name/path.

getLeftHandSide

public static PropertyRef getLeftHandSide(Expression expr)
                                   throws IllegalArgumentException

Deprecated.

Get the left-hand-side of a valid leaf node, which should be a PropertyRef

Throws:

IllegalArgumentException

getLogicalComparator

public static String getLogicalComparator(Expression expr)
                                   throws IllegalArgumentException

Deprecated.

Get the syntax logical comparator textual operator for the given branch node.

Throws:

IllegalArgumentException

getOrdinalValue

public static int getOrdinalValue(char ch)

Deprecated.

Get the ordinal (Unicode) value of a character.

getRightHandSide

public static Object getRightHandSide(Expression expr)
                               throws IllegalArgumentException

Deprecated.

Get the right-hand-side of a valid leaf node.

Throws:

IllegalArgumentException

getSubExpression

public static Expression getSubExpression(Expression expr,
                                          int count)
                                   throws IllegalArgumentException

Deprecated.

Throws:

IllegalArgumentException

isHexString

public static boolean isHexString(String str)

Deprecated.

Determine if a string contains only ASCII hexidecimal characters ([0-9a-fA-F]).

isLogicalNot

public static Expression isLogicalNot(Expression expr)

Deprecated.

Tell if an expression is really a logical not and, if so, returned the contained expression.

Parameters:

expr - the expression.

Returns:

the contained expressions if expr is a logical not, null otherwise.

isValidBranchNode

public static boolean isValidBranchNode(Expression expr)

Deprecated.

Tell if an expression is a valid content branch node type.

isValidLeafNode

public static boolean isValidLeafNode(Expression expr)

Deprecated.

Tell if an expression is a valid content leaf node type.

join

public static LogicalAnd join(Expression expr1,
                              Expression expr2)

Deprecated.

Join together two expression via an AND expression.

Parameters:

expr1 - the first expression.

expr2 - the second expression.

Returns:

a LogicalAnd of the two expressions.

normalize

public static Expression normalize(Expression expr)
                            throws IllegalArgumentException

Deprecated.

Normalize an Expression.

This will recursively remove branches that contain only one Expression (which are boolean equivelant to the one child expression) or that contain no children (which are considered empty).

Parameters:

expr - the incoming expression.

Returns:

the normalized expression, null if normalized to nothing.

Throws:

IllegalArgumentException - thrown if the expression is not a valid content expression.

parse

public static Expression parse(String queryStr)
                        throws ExpressionHelper.ParseException,
                               IllegalArgumentException

Deprecated.

Convert a query expression string into an Expression object.

The string should follow the query syntax specified in the Personalization Server documentation. The expression syntax is tree-based, with each leaf in the tree beinging of the form "property comparator value" (e.g. "identifier == '1234'").

Property (LHS)

This specifies the object property to match against. To specify a property name which contains non-identifier characters (e.g. whitespace, double quotes, dashes), you can use the "toProperty('property name')" form in the left-hand-side. To specify property set names as part of the property name, either use the "properyset.name" form or the "toProperty('propertyset', 'property')" form in the left-hand-side.

Comparators

The valid comparision operators are = (or ==), !=, <, >, <=, >=, "like", "likeignorecase" and "contains". The "like" and "likeignorecase" operator expects the pattern (which is the value of the leaf) to use * (match all) and ? (match any); "like" and "likeignorecase" also is only expected to work against String values, although it might work with other datatypes depending upon the search implementation. "like" operator does case-sensitive pattern match, while "likeignorecase" operator does case- insensitive pattern match. The "contains" operator is only expected to work against multi-valued properties, although it might work with other datatypes depending upon the search implementation.

Value (RHS)

• String literal values are enclosed in single quotes (back-slash is the quoting character, unicode characters not supported). Additionally, unicode (e.g. "\u6565"), octal (e.g. "\7", "\65", "\377"), and standard Java escape sequences (e.g. "\n", "\r", "\b") are allowed in the string literals.
• Boolean literals are either the "true" or "false" keyword (without quotes).
• Number literals are Java form (scientific notation is supported).
• Time literals are presented in "toDate(['formatStr'], 'dateStr')" format. formatStr must be a valid SimpleDateFormat format string; if omitted, 'MM/dd/yyyy HH:mm:ss z' is used. Also, the "now" keyword specifies the time at which the expression was created.
• Collections cannot be represented in the expression syntax.
• References to user, request, or session properties are represented as such:

  
   <type>Property(<propertyset>, <propertyname>)
   
   where <type> is one of 'user', 'request',
   or 'session', <propertyset> is the property set name
   and follows the rules for string literals.
   <propertyname> is the property name and follows the
   rules for string literals.
  
   References to properties should not be passed into a
   DocumentManager class. Expression which contain references to
   properties should be realized into a searchable expression via the
   realize() method.
   

Each branch in the tree is comprised of 1 or more leafs or branches separated by either "&&" (boolean AND) or "||" (boolean OR). They can be enclosed in parenthesis for clearity and ordering (AND has precendance over OR). Additionally, "!" marks a branch as using negative logic (boolean NOT). The "!" operator can only be used preceding an open parenthesis.

Examples of valid expression strings:

• identifier == '00099abv48932ds'
• language == userProp('MyProperties', 'userPreferredLang')
• ((UserAge <= 35 && colors contains 'red') || (UserAge > 35 && !(colors contains 'black')) && mimeType == 'text/html'
• toProperty('MyApp', 'Launch Date') < now && !(MyApp.expireDate > toDate('HH:mm:ss MM-dd-yyyy', '12:12:12 12/12/2002'))

In the resulting expression tree, the following caveats apply for it to be valid for the ContentManager:

• Each branch node can only be a LogicalAnd, LogicalOr, LogicalMulitAnd, or LogicalMultiOr. Any other branch node type is invalid.
• Each leaf node can only be an Equals, GreaterOrEquals, GreaterThan, LessOrEquals, LessThan, NotEquals, StringLike, CollectionContains, or CollectionsContainsAll. Any other branch node type is invalid.
• Any valid branch or leaf node may be contained in a LogicalNot node.
• In each leaf node, the left-hand-side will always be a PropertyRef node, which must contain Strings for getPropertySet() and getPropertyName(). In non-realized expression, a leaf node can be a UserPropertyRef, RequestPropertyRef, or SessionPropertyRef to represent a reference to an external property. ContentManagers should not receive non-realized expression, and, therefore, should not receive these objects; they are free to raise an exception if one is found.
• The right-hand-side of Equals, NotEquals, GreaterOrEquals, GreaterThan, LessOrEquals, LessThan, or CollectionContains leaf nodes can be a Collection, Long, Double, String, or Timestamp.
• The right-hand-side of StringLike leaf nodes can be a String. Anything else is invalid.
• The right-hand-side of CollectionsContainsAll leaf nodes can be a Collection. Anything else is invalid.

Parameters:

queryStr - the query expression string

Returns:

an Expression object representing (null if queryStr is a null expression).

Throws:

ExpressionHelper.ParseException - thrown on a an invalid expression query or a parser error.

IllegalArgumentException - thrown on a general error.

See Also:

convertException(java.lang.Exception), normalize(com.bea.p13n.expression.Expression)

print

public static void print(PrintWriter out,
                         Expression expr)
                  throws IllegalArgumentException

Deprecated.

Print a string representation of the given expression.

Pretty much, a string generated from this method can be parse()'ed into the equivalent (not neccessarily identical) expression tree.

Parameters:

out - the output writer.

expr - the expression.

Throws:

IllegalArgumentException - thrown if the given expression is not a valid content expression.

printBranchNode

public static void printBranchNode(PrintWriter out,
                                   Expression expr)

Deprecated.

Return a string representation of the given expression branch.

printLeafNode

public static void printLeafNode(PrintWriter out,
                                 Expression expr)
                          throws IllegalArgumentException

Deprecated.

Return a string representation of the given leaf expression node.

Throws:

IllegalArgumentException

printTree

public static void printTree(int depth,
                             PrintWriter out,
                             Expression expr)

Deprecated.

For debug purposes, print the given expression as a tree at the given depth.

Parameters:

depth - the depth of this expression in the tree.

out - the output stream to print on.

expr - the expression.

printTree

public static void printTree(PrintWriter out,
                             Expression expr)

Deprecated.

For debug purposes, print the given expression as a tree.

Parameters:

out - the output stream to print on.

expr - the expression.

realize

public static Expression realize(Expression expr,
                                 PropertyProvider props)
                          throws IllegalArgumentException

Deprecated.

Realize an expression, which can contain property references, into an an expression which contains only literal values and can be sent to a ContentManager.

This will modify the passed in expression.

Parameters:

expr - the expression to realize.

props - the object which provides values for property references.

Returns:

the modified expression

Throws:

IllegalArgumentException - thrown if the expr is not a valid content expression or contain a reference to an unknown property type.

toString

public static String toString(Expression expr)
                       throws IllegalArgumentException

Deprecated.

Get a string representation of the given expression.

Pretty much, a string generated from this method can be parse()'ed into the equivalent (not neccessarily identical) expression tree.

Parameters:

expr - the expression.

Returns:

the query syntax representation of the expression.

Throws:

IllegalArgumentException - thrown if the given expression is not a valid content expression.

toStringLiteral

public static String toStringLiteral(String in)

Deprecated.

Get an ASCII String literal from a Java string.

This will quote some special characters with back-slashes.

The output of this can be sent through fromStringLiteral(java.lang.String) to result in the original String.

toTree

public static String toTree(Expression expr)

Deprecated.

For debug purposes, return a tree representation of the given expression.