org.z3950.zing.cql
Class CQLNode

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

Direct Known Subclasses:

CQLBooleanNode, CQLPrefixNode, CQLRelation, CQLSortNode, CQLTermNode

public abstract class CQLNode
extends java.lang.Object

Represents a node in a CQL parse-tree.

Version:

$Id: CQLNode.java,v 1.26 2007-07-03 13:36:03 mike Exp $

Field Summary

protected static int	APPLICATION
static byte	BITSTRING
static byte	BOOLEAN
protected static int	CONSTRUCTED
protected static int	CONTEXT
static byte	ENUMERATED
static byte	EXTERNAL
static byte	GENERALSTRING
static byte	INTEGER
static byte	NULL
static byte	OBJECTDESCRIPTOR
static byte	OBJECTIDENTIFIER
static byte	OCTETSTRING
protected static int	PRIMITIVE
protected static int	PRIVATE
static byte	SEQUENCE
static byte	SET
protected static int	UNIVERSAL
static byte	VISIBLESTRING

Method Summary

java.lang.String	getResultSetName() Returns the name of the result-set to which this query is a reference, if and only if the entire query consists only of a result-set reference.
protected static java.lang.String	indent(int level) Returns a String of spaces for indenting to the specified level.
protected static int	lenLen(int length) Get the length needed to represent the given length.
protected static byte[]	makeOID(java.lang.String oid)
static byte[]	makeQuery(CQLNode root, java.util.Properties properties)
protected static int	numLen(long num) Get the length needed to represent the given number.
static int	putLen(int len, byte[] record, int offset) Put a length directly into a BER record.
protected static int	putNum(long num, byte[] record, int offset) Put a number into a given buffer
protected static int	putTag(int asn1class, int fldid, int form, byte[] record, int offset)
protected static java.lang.String	renderPrefixes(int level, java.util.Vector prefixes)
protected static java.lang.String	renderSortKeys(int level, java.util.Vector<ModifierSet> sortkeys)
abstract java.lang.String	toCQL() Decompiles a parse-tree into a CQL query.
abstract java.lang.String	toPQF(java.util.Properties config) Renders a parse-tree into a Yaz-style PQF string.
abstract byte[]	toType1BER(java.util.Properties config) Renders a parser-tree into a BER-endoded packet representing an equivalent Z39.50 Type-1 query.
java.lang.String	toXCQL(int level) Translates a parse-tree into an XCQL document.
java.lang.String	toXCQL(int level, java.util.Vector<CQLPrefix> prefixes)
abstract java.lang.String	toXCQL(int level, java.util.Vector<CQLPrefix> prefixes, java.util.Vector<ModifierSet> sortkeys)
protected static java.lang.String	xq(java.lang.String str) Returns the argument String quoted for XML.

Methods inherited from class java.lang.Object

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

Field Detail

UNIVERSAL

protected static final int UNIVERSAL

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Constant Field Values

APPLICATION

protected static final int APPLICATION

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CONTEXT

protected static final int CONTEXT

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PRIVATE

protected static final int PRIVATE

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PRIMITIVE

protected static final int PRIMITIVE

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Constant Field Values

CONSTRUCTED

protected static final int CONSTRUCTED

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Constant Field Values

BOOLEAN

public static final byte BOOLEAN

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Constant Field Values

INTEGER

public static final byte INTEGER

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BITSTRING

public static final byte BITSTRING

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Constant Field Values

OCTETSTRING

public static final byte OCTETSTRING

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NULL

public static final byte NULL

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OBJECTIDENTIFIER

public static final byte OBJECTIDENTIFIER

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Constant Field Values

OBJECTDESCRIPTOR

public static final byte OBJECTDESCRIPTOR

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Constant Field Values

EXTERNAL

public static final byte EXTERNAL

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Constant Field Values

ENUMERATED

public static final byte ENUMERATED

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SEQUENCE

public static final byte SEQUENCE

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SET

public static final byte SET

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Constant Field Values

VISIBLESTRING

public static final byte VISIBLESTRING

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Constant Field Values

GENERALSTRING

public static final byte GENERALSTRING

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Constant Field Values

Method Detail

getResultSetName

public java.lang.String getResultSetName()

Returns the name of the result-set to which this query is a reference, if and only if the entire query consists only of a result-set reference. If it's anything else, including a boolean combination of a result-set reference with something else, then null is returned instead.

Returns:

the name of the referenced result-set

toXCQL

public java.lang.String toXCQL(int level)

Translates a parse-tree into an XCQL document.

Parameters:

level - The number of levels to indent the top element of the XCQL document. This will typically be 0 when invoked by an application; it takes higher values when this method is invoked recursively for nodes further down the tree.

Returns:

A String containing an XCQL document equivalent to the parse-tree whose root is this node.

toXCQL

public java.lang.String toXCQL(int level,
                               java.util.Vector<CQLPrefix> prefixes)

toXCQL

public abstract java.lang.String toXCQL(int level,
                                        java.util.Vector<CQLPrefix> prefixes,
                                        java.util.Vector<ModifierSet> sortkeys)

renderPrefixes

protected static java.lang.String renderPrefixes(int level,
                                                 java.util.Vector prefixes)

renderSortKeys

protected static java.lang.String renderSortKeys(int level,
                                                 java.util.Vector<ModifierSet> sortkeys)

toCQL

public abstract java.lang.String toCQL()

Decompiles a parse-tree into a CQL query.

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 abstract java.lang.String toPQF(java.util.Properties config)
                                throws PQFTranslationException

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.

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

indent

protected static java.lang.String indent(int level)

Returns a String of spaces for indenting to the specified level.

xq

protected static java.lang.String xq(java.lang.String str)

Returns the argument String quoted for XML. For example, each occurrence of < is translated to &lt;.

toType1BER

public abstract byte[] toType1BER(java.util.Properties config)
                           throws PQFTranslationException

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.

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

putTag

protected static final int putTag(int asn1class,
                                  int fldid,
                                  int form,
                                  byte[] record,
                                  int offset)

putLen

public static final int putLen(int len,
                               byte[] record,
                               int offset)

Put a length directly into a BER record.

Parameters:

len - length to put into record

Returns:

the new, incremented value of the offset parameter.

lenLen

protected static final int lenLen(int length)

Get the length needed to represent the given length.

Parameters:

length - determine length needed to encode this

Returns:

length needed to encode given length

numLen

protected static final int numLen(long num)

Get the length needed to represent the given number.

Parameters:

num - determine length needed to encode this

Returns:

length needed to encode given number

putNum

protected static final int putNum(long num,
                                  byte[] record,
                                  int offset)

Put a number into a given buffer

Parameters:

num - number to put into buffer

record - buffer to use

offset - offset into buffer

Returns:

the new, incremented value of the offset parameter.

makeOID

protected static final byte[] makeOID(java.lang.String oid)

makeQuery

public static final byte[] makeQuery(CQLNode root,
                                     java.util.Properties properties)
                              throws PQFTranslationException

Throws:

PQFTranslationException