EqualityOperand.java

/*******************************************************************************
 * Copyright 2012 Apigee Corporation
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.usergrid.persistence.query.tree;

/**
 * A base class for any equality expression.  Expressions must have a property and a value.  
 * Examples are >=, >, =, <, <=,
 *  
 * @author tnine
 *
 */
public abstract class EqualityOperand extends Operand {

  protected Property property;
  protected Literal literal;
  
  /**
   * @param property
   * @param literal
   */
  public EqualityOperand(Property property, Literal literal) {
    super();
    this.property = property;
    this.literal = literal;
  }
  

}

Float.java

/*******************************************************************************
 * Copyright 2012 Apigee Corporation
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.usergrid.persistence.query.tree;

import org.antlr.runtime.Token;



/**
 * @author tnine
 *
 */
public class Float extends Literal {

  /**
   * @param t
   */
  protected Float(Token t) {
    super(t);
  }

}

LessThan.java

/*******************************************************************************
 * Copyright 2012 Apigee Corporation
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.usergrid.persistence.query.tree;


/**
 * @author tnine
 * 
 */
public class LessThan extends EqualityOperand{

  /**
   * @param property
   * @param literal
   */
  public LessThan(Property property, Literal literal) {
    super(property, literal);
  }

 
}

Property.java

/*******************************************************************************
 * Copyright 2012 Apigee Corporation
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.usergrid.persistence.query.tree;

import org.antlr.runtime.Token;


/**
 * A property
 * @author tnine
 *
 */
public class Property extends Literal {

  protected Property(Token t) {
    super(t);
  }

}

QueryFilter.g

grammar QueryFilter;
//NOTES:  '^' denotes operator, all others in the string become operands


options {
    output=AST;
//    ASTLabelType=CommonTree;
}

@header {
package org.usergrid.persistence.query.tree;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.usergrid.persistence.Query;
import org.usergrid.persistence.Query.FilterPredicate;
import org.usergrid.persistence.Query.SortPredicate;

}

@lexer::header {
package org.usergrid.persistence.query.tree;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

}

@members {
	Query query = new Query();

  private static final Logger logger = LoggerFactory
      .getLogger(QueryFilterLexer.class);

	@Override
	public void emitErrorMessage(String msg) {
		logger.info(msg);
	}
}
  
@lexer::members {

  private static final Logger logger = LoggerFactory
      .getLogger(QueryFilterLexer.class);

	@Override
	public void emitErrorMessage(String msg) {
		logger.info(msg);
	}
}

ID  :	('a'..'z'|'A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'0'..'9'|'_'|'.')*
    ;

INT :	('-')? '0'..'9'+
    ;

FLOAT
    :  ('-')? ( ('0'..'9')+ '.' ('0'..'9')* EXPONENT?
    |   '.' ('0'..'9')+ EXPONENT?
    |   ('0'..'9')+ EXPONENT)
    ;
    
STRING
    :  '\'' ( ESC_SEQ | ~('\\'|'\'') )* '\''
    ;
    
fragment
BOOLEAN :	('true' |'false');
    
UUID :	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT '-' 
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT '-' 
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT '-' 
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT '-' 
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
	HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
	;

fragment
EXPONENT : ('e'|'E') ('+'|'-')? ('0'..'9')+ ;

fragment
HEX_DIGIT : ('0'..'9'|'a'..'f'|'A'..'F') ;

fragment
ESC_SEQ
    :   '\\' ('b'|'t'|'n'|'f'|'r'|'\"'|'\''|'\\')
    |   UNICODE_ESC
    |   OCTAL_ESC
    ;

fragment
OCTAL_ESC
    :   '\\' ('0'..'3') ('0'..'7') ('0'..'7')
    |   '\\' ('0'..'7') ('0'..'7')
    |   '\\' ('0'..'7')
    ;

fragment
UNICODE_ESC
    :   '\\' 'u' HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
    ;

WS : (' ' | '\t' | '\n' | '\r' | '\f')+  {$channel=HIDDEN;};

LT 	:	'<' | 'lt';

LTE	:	'<=' |  'lte';

EQ  : '=' | 'eq';

GT 	:	'>' | 'gt';

GTE	:	'>=' |  'gte';	

//NE : '!=';



property 
	:	 ID<Property>;
	
value   : BOOLEAN<Boolean> | STRING<StringQuery> | INT<Integer> | FLOAT<Float> | UUID<UUID>;
	
//begin equality expressions

//mathmatical equality operations
equalityop :	
  property ( LT<LessThan>
	| LTE <LessThanEqual>^
	| EQ <Equal>^
	| GT <GreaterThan>^
	| GTE <GreaterThanEqual>^) value {
	  
	
	};
//	| NE 

//geo location search
locationop:
  property 'within'<Within>^ FLOAT<Float> 'of' FLOAT<Float> ',' FLOAT<Float> ;
  
//string search
containsop : 
  property 'contains'<Contains>^ STRING<StringQuery> ;
  
//
operation :
 '('! expression ')'! | equalityop | locationop | containsop;

//negations of expressions
notexp :
 'not'^ operation|operation;
    

//and expressions contain operands.  These should always be closer to the leaves of a tree, it allows
//for faster result intersection sooner in the query execution
andexp :
 notexp ('and'^ notexp)*;
 
//or expression should always be after AND expressions.  This will give us a smaller result set to union when evaluating trees
orexp :
 andexp ('or'^ andexp)*;

//root level boolean expression
expression:
  orexp;

//end expressions

//begin order clauses

//direction for ordering
direction  : ('asc' | 'desc');

//order clause
order
  : (property direction?);

//end order clauses
  
//Begin select clauses

select_subject
  : ID {

  query.addSelect($select_subject.text);

};

select_assign_target 
  : ID;
  
select_assign_source 
  : ID;    

select_assign
  : select_assign_target ':' select_assign_source {

  query.addSelect($select_assign_source.text, $select_assign_target.text);

};

select_expr 
  : ('*' | select_subject (',' select_subject) * | '{' select_assign (',' select_assign) * '}');  
   
//end select clauses

ql returns [Query q]
  : 'select' select_expr ('where' expression )? ('order by' order (',' order)*)? {

//q = query;

//TODO other stuff
};