condor.classad
Class Query

Object
  |
  +--condor.classad.Query

public class Query

extends Object

A parsed "query" in a very simple ad hoc query language inspired by SQL. This is a hack desiged to test the ClassAd machinery by sending a query to Condor Collector and interpreting the results. A query has the form

     Query: 'select' SelectClause 'from' Identifier WhereClause
     SelectClause: '*' | SelectionList
     SelectionList: [ SelectionList ',' ] Identifier [ '=' Expression ]
     WhereClause : [ 'where' Expression ]
 

Version:

2.0

Author:

Marvin Solomon

Field Summary

String	fromClause The "from" clause (original case preserved).
Expr[]	selectClause The expressions in the SelectionClause.
String[]	selectNames The Identifiers in the SelectionClause.
Expr	whereClause The "where" clause or null if the "where" clause was omitted.

Constructor Summary

Query(Expr[] s, String[] n, String f, Expr w)
Construct a query from its components.

Method Summary

static Query	parse(ClassAdParser parser) Create a Query from an exsiting parser.
static Query	parse(InputStream s) Create a Query by parsing input from an InputStream.
static Query	parse(Reader s) Create a Query by parsing input from a Reader.
static Query	parse(String s) Create a Query by parsing a String.
String	toString()

Methods inherited from class Object

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

Field Detail

selectClause

public final Expr[] selectClause

The expressions in the SelectionClause. If the clause was "*", this field is null. Otherwise, it has one element for each "Identifier = Expression" or "Identifier" in the SelectionList. The element is the Expression if present; otherwise, it is AttrRef expression corresponding to the Identifier.

selectNames

public final String[] selectNames

The Identifiers in the SelectionClause. If the clause was "*", this field is null. Otherwise, it has one element for each "Identifier = Expression" or "Identifier" in the SelectionList. If the Expression is present, the element is the original Identifier (with case preserved). Otherwise, it is null.

fromClause

public String fromClause

The "from" clause (original case preserved).

whereClause

public Expr whereClause

The "where" clause or null if the "where" clause was omitted.

Constructor Detail

Query

public Query(Expr[] s,
             String[] n,
             String f,
             Expr w)

Construct a query from its components.

Parameters:

s - the "select" clause expressions.

n - the "select" clause identifiers.

f - the "from" clause.

w - the "where" clause (or null).

Method Detail

parse

public static Query parse(InputStream s)

Create a Query by parsing input from an InputStream.

Parameters:

s - the input source.

Returns:

a new Query object.

parse

public static Query parse(Reader s)

Create a Query by parsing input from a Reader.

Parameters:

s - input source.

Returns:

a new Query object.

parse

public static Query parse(String s)

Create a Query by parsing a String.

Parameters:

s - the input source.

Returns:

a new Query object.

parse

public static Query parse(ClassAdParser parser)

Create a Query from an exsiting parser.

Parameters:

parser - the input source.

Returns:

a new Query object.

toString

public String toString()

Overrides:

toString in class Object