com.onwbp.adaptation

Class XPathFilter

java.lang.Object

com.onwbp.adaptation.XPathFilter

public final class XPathFilter
extends Object

Defines an XPath predicate. The factory methods allow internal caching for a better performance.

Code sample:

 XPathFilter xpf = XPathFilter.newFilter("./field=$param");

 Request request = tableA.createRequest();
 request.setXPathFilter(xpf);
 request.setXPathParameter("param", "A");
 request.execute();

 request = tableB.createRequest();
 request.setXPathFilter(xpf);
 request.setXPathParameter("param", "B");
 request.execute();
 

Since:

5.7.0

See Also:

newFilter(String), Request.setXPathFilter(XPathFilter), Request.setXPathParameter(String, Object), Supported XPath syntax

Method Summary

Modifier and Type	Method and Description
String	getPredicateExpression()
static XPathFilter	newFilter(boolean isCached, String aPredicateExpression) Builds an XPath filter.
static XPathFilter	newFilter(String aPredicateExpression) Builds a cache-enabled XPath predicate.
String	toString()
void	validateForTableNode(SchemaNode aTableNode) Checks if a predicate expression is valid according to the schema of the table.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

newFilter

public static XPathFilter newFilter(String aPredicateExpression)

Builds a cache-enabled XPath predicate.

This method is equivalent to:

 XPathFilter.newFilter(true, aPredicateExpression);
 

Warning: if many cached predicates with quite specific values are cached, and are not often reused, the memory cost could counter-balance the performance gain.

See Also:

Request.setXPathFilter(XPathFilter)

newFilter

public static XPathFilter newFilter(boolean isCached,
                                    String aPredicateExpression)

Builds an XPath filter.

Performance considerations: If the specified predicate must be often reused by multiple Request objects, it is recommended to enable caching. Parameterized expressions also help reuse.

Warning: however, if many cached predicates with quite specific values are cached (isCached = true), but are not reused often, the memory cost could counter-balance the performance gain. More specifically, if a predicate is used only once, it is not recommended to use caching.

Parameters:

isCached - If true, the filter is cached in order to be reused when the same predicate expression is applied. If false, the filter is not cached and thus it cannot be reused.

aPredicateExpression - XPath predicate expression to apply to the table records.

See Also:

Request.setXPathFilter(XPathFilter)

getPredicateExpression

public String getPredicateExpression()

validateForTableNode

public void validateForTableNode(SchemaNode aTableNode)
                          throws IllegalArgumentException,
                                 MalformedXPathExpressionException

Checks if a predicate expression is valid according to the schema of the table.

Throws:

IllegalArgumentException - if the specified argument is not defined or if the specified argument is not a table node.

MalformedXPathExpressionException - if the predicate is malformed or if the predicate is not valid according to the schema of the table.

Since:

5.8.0

See Also:

newFilter(String), Request.setXPathFilter(XPathFilter)

toString

public String toString()

Overrides:

toString in class Object