org.z3950.zing.cql
Class CQLPrefixNode

java.lang.Object
  org.z3950.zing.cql.CQLNode
      org.z3950.zing.cql.CQLPrefixNode

public class CQLPrefixNode
extends CQLNode

Represents a prefix node in a CQL parse-tree.

Field Summary

Fields inherited from class org.z3950.zing.cql.CQLNode

APPLICATION, BITSTRING, BOOLEAN, CONSTRUCTED, CONTEXT, ENUMERATED, EXTERNAL, GENERALSTRING, INTEGER, NULL, OBJECTDESCRIPTOR, OBJECTIDENTIFIER, OCTETSTRING, PRIMITIVE, PRIVATE, SEQUENCE, SET, UNIVERSAL, VISIBLESTRING

Constructor Summary

CQLPrefixNode(String name, String identifier, CQLNode subtree)
Creates a new CQLPrefixNode inducing a mapping from the specified index-set name to the specified identifier across the specified subtree.

Method Summary

CQLPrefix	getPrefix() The prefix definition that governs the subtree.
CQLNode	getSubtree() The root of a parse-tree representing the part of the query that is governed by this prefix definition.
String	toCQL() Decompiles a parse-tree into a CQL query.
String	toPQF(Properties config) Renders a parse-tree into a Yaz-style PQF string.
byte[]	toType1BER(Properties config) Renders a parser-tree into a BER-endoded packet representing an equivalent Z39.50 Type-1 query.

Methods inherited from class org.z3950.zing.cql.CQLNode

getResultSetName, lenLen, makeOID, makeQuery, numLen, putNum, putTag, toString, toXCQL

Methods inherited from class java.lang.Object

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

Constructor Detail

CQLPrefixNode

public CQLPrefixNode(String name,
                     String identifier,
                     CQLNode subtree)

Creates a new CQLPrefixNode inducing a mapping from the specified index-set name to the specified identifier across the specified subtree.

Method Detail

getPrefix

public CQLPrefix getPrefix()

The prefix definition that governs the subtree.

getSubtree

public CQLNode getSubtree()

The root of a parse-tree representing the part of the query that is governed by this prefix definition.

toCQL

public String toCQL()

Description copied from class: CQLNode

Decompiles a parse-tree into a CQL query.

Specified by:

toCQL in class CQLNode

Returns:

A String containing a CQL query equivalent to the parse-tree whose root is this node, so that compiling that query will yield an identical tree.

toPQF

public String toPQF(Properties config)
             throws PQFTranslationException

Description copied from class: CQLNode

Renders a parse-tree into a Yaz-style PQF string. PQF, or Prefix Query Format, is a cryptic but powerful notation that can be trivially mapped, one-to-one, int Z39.50 Type-1 and Type-101 queries. A specification for the format can be found in Chapter 7 (Supporting Tools) of the YAZ manual.

Specified by:

toPQF in class CQLNode

Parameters:

config - A Properties object containing configuration information that specifies the mapping from CQL indexes, relations, etc. to Type-1 attributes. The mapping specification is described in the CQL-Java distribution's sample PQF-mapping configuration file, etc/pqf.properties, which see.

Returns:

A String containing a PQF query equivalent to the parse-tree whose root is this node.

Throws:

PQFTranslationException

toType1BER

public byte[] toType1BER(Properties config)
                  throws PQFTranslationException

Description copied from class: CQLNode

Renders a parser-tree into a BER-endoded packet representing an equivalent Z39.50 Type-1 query. If you don't know what that means, then you don't need this method :-) This is useful primarily for SRW-to-Z39.50 gateways.

Specified by:

toType1BER in class CQLNode

Parameters:

config - A Properties object containing configuration information that specifies the mapping from CQL indexes, relations, etc. to Type-1 attributes. The mapping specification is described in the CQL-Java distribution's sample PQF-mapping configuration file, etc/pqf.properties, which see.

Returns:

A byte array containing the BER packet.

Throws:

PQFTranslationException

See Also:

ftp://ftp.rsasecurity.com/pub/pkcs/ascii/layman.asc