1.1 --- a/generaldb/src/main/java/org/openrdf/sail/generaldb/evaluation/GeneralDBEvaluation.java	Mon Sep 22 15:13:33 2014 +0300
     1.2 +++ b/generaldb/src/main/java/org/openrdf/sail/generaldb/evaluation/GeneralDBEvaluation.java	Mon Sep 22 16:24:07 2014 +0300
     1.3 @@ -291,37 +291,41 @@
     1.4  			throw new UnsupportedExtensionFunctionException("Extension function " + fc.getURI()+ " is not supported.");
     1.5  		}
     1.6  		
     1.7 -		// get the first argument of the function call
     1.8 -		ValueExpr left = fc.getArgs().get(0);
     1.9 -
    1.10 -		// evaluated first argument of function
    1.11 -		Value leftResult = null;
    1.12 +		try {
    1.13 +			if (fc.getArgs().size() == 0) {
    1.14 +				throw new NoSuchMethodException("too few arguments");
    1.15 +			}
    1.16  		
    1.17 -		// evaluated second argument of function (if any)
    1.18 -		Value rightResult = null;
    1.19 -
    1.20 -		// evaluated third argument of function (if any)
    1.21 -		Value thirdResult = null;
    1.22 +			// get the first argument of the function call
    1.23 +			ValueExpr left = fc.getArgs().get(0);
    1.24 +		
    1.25 +			// evaluated first argument of function
    1.26 +			Value leftResult = null;
    1.27 +			
    1.28 +			// evaluated second argument of function (if any)
    1.29 +			Value rightResult = null;
    1.30 +		
    1.31 +			// evaluated third argument of function (if any)
    1.32 +			Value thirdResult = null;
    1.33 +					
    1.34 +			// evaluate first argument
    1.35 +			leftResult = evaluate(left, bindings);
    1.36 +			
    1.37 +			// function call with 2 or more arguments, evaluate the second one now
    1.38 +			// see distance function as example
    1.39 +			if ( fc.getArgs().size() >= 2 )
    1.40 +			{
    1.41 +				ValueExpr right = fc.getArgs().get(1);
    1.42 +				rightResult = evaluate(right, bindings);
    1.43  				
    1.44 -		// evaluate first argument
    1.45 -		leftResult = evaluate(left, bindings);
    1.46 +				if (fc.getArgs().size() == 3) {
    1.47 +					ValueExpr third = fc.getArgs().get(2);
    1.48 +					thirdResult = evaluate(third, bindings);
    1.49 +				}
    1.50 +			}
    1.51  		
    1.52 -		// function call with 2 or more arguments, evaluate the second one now
    1.53 -		// see distance function as example
    1.54 -		if ( fc.getArgs().size() >= 2 )
    1.55 -		{
    1.56 -			ValueExpr right = fc.getArgs().get(1);
    1.57 -			rightResult = evaluate(right, bindings);
    1.58 +			// having evaluated the arguments, evaluate the function now
    1.59  			
    1.60 -			if (fc.getArgs().size() == 3) {
    1.61 -				ValueExpr third = fc.getArgs().get(2);
    1.62 -				thirdResult = evaluate(third, bindings);
    1.63 -			}
    1.64 -		}
    1.65 -
    1.66 -		// having evaluated the arguments of the function, evaluate the function
    1.67 -		try {
    1.68 -
    1.69  			//
    1.70  			// SPATIAL METRIC FUNCTIONS
    1.71  			//
    1.72 @@ -336,6 +340,9 @@
    1.73  				} 
    1.74  				else if(function instanceof DistanceFunc)
    1.75  				{
    1.76 +					// check required number of arguments
    1.77 +					checkArgs(leftResult, rightResult, thirdResult, 3);
    1.78 +					
    1.79  					// get the second geometry
    1.80  					Geometry rightGeom = getValueAsStrabonPolyhedron(rightResult).getGeometry();
    1.81  					
    1.82 @@ -503,19 +510,56 @@
    1.83  		}
    1.84  	}
    1.85  
    1.86 -	public StrabonPolyhedron spatialConstructPicker(Function function, Value left, Value right, Value thirdResult) throws Exception
    1.87 +	/**
    1.88 +	 * @param leftResult
    1.89 +	 * @param rightResult
    1.90 +	 * @param thirdResult
    1.91 +	 * @param size
    1.92 +	 * @throws NoSuchMethodException 
    1.93 +	 */
    1.94 +	private void checkArgs(Value leftResult, Value rightResult, Value thirdResult, int size) throws NoSuchMethodException {
    1.95 +		if (size == 0) {
    1.96 +			throw new NoSuchMethodException("too few arguments.");
    1.97 +			
    1.98 +		} else {
    1.99 +			if (size >= 1 && leftResult == null) {
   1.100 +				throw new NoSuchMethodException("expecting an argument.");
   1.101 +			}
   1.102 +			
   1.103 +			if (size >= 2 && rightResult == null) {
   1.104 +				throw new NoSuchMethodException("expecting a second argument.");
   1.105 +			}
   1.106 +			
   1.107 +			if (size >= 3 && thirdResult == null) {
   1.108 +				throw new NoSuchMethodException("expecting a third argument.");
   1.109 +				
   1.110 +			}
   1.111 +			
   1.112 +			if (size > 3) {
   1.113 +				throw new NoSuchMethodException("too many arguments.");
   1.114 +			}
   1.115 +		}
   1.116 +	}
   1.117 +
   1.118 +	public StrabonPolyhedron spatialConstructPicker(Function function, Value left, Value right, Value third) throws Exception
   1.119  	{
   1.120  		StrabonPolyhedron leftArg = getValueAsStrabonPolyhedron(left);
   1.121  		if(function.getURI().equals(GeoConstants.stSPARQLunion))
   1.122  		{
   1.123 +			// check required number of arguments
   1.124 +			checkArgs(left, right, third, 2);
   1.125 +			
   1.126  			StrabonPolyhedron rightArg = getValueAsStrabonPolyhedron(right);
   1.127  			return StrabonPolyhedron.union(leftArg, rightArg);
   1.128  		}
   1.129  		else if (function instanceof BufferFunc) {
   1.130 +			// check required number of arguments
   1.131 +			checkArgs(left, right, third, 3);
   1.132 +						
   1.133  			// TODO implement computation of the buffer in meters
   1.134  			// you'll get the type (degrees/meter) from the thirdResult, which
   1.135  			// would be a URI.
   1.136 -			if (OGCConstants.OGCmetre.equals(thirdResult.stringValue())) {
   1.137 +			if (OGCConstants.OGCmetre.equals(third.stringValue())) {
   1.138  				logger.info("[GeneraDBEvaluation] Computation of {} will be done in degrees.", function.getURI());
   1.139  			}
   1.140  			
   1.141 @@ -532,6 +576,9 @@
   1.142  		}
   1.143  		else if(function.getURI().equals(GeoConstants.stSPARQLtransform))
   1.144  		{
   1.145 +			// check required number of arguments
   1.146 +			checkArgs(left, right, third, 2);
   1.147 +						
   1.148  			if(right instanceof URIImpl)
   1.149  			{
   1.150  				URIImpl srid = (URIImpl) right;
   1.151 @@ -562,16 +609,25 @@
   1.152  		}
   1.153  		else if(function.getURI().equals(GeoConstants.stSPARQLintersection))
   1.154  		{
   1.155 +			// check required number of arguments
   1.156 +			checkArgs(left, right, third, 2);
   1.157 +			
   1.158  			StrabonPolyhedron rightArg = getValueAsStrabonPolyhedron(right);
   1.159  			return StrabonPolyhedron.intersection(leftArg, rightArg);
   1.160  		}
   1.161  		else if(function.getURI().equals(GeoConstants.stSPARQLdifference))
   1.162  		{
   1.163 +			// check required number of arguments
   1.164 +			checkArgs(left, right, third, 2);
   1.165 +			
   1.166  			StrabonPolyhedron rightArg = getValueAsStrabonPolyhedron(right);
   1.167  			return StrabonPolyhedron.difference(leftArg, rightArg);		
   1.168  		}
   1.169  		else if(function.getURI().equals(GeoConstants.stSPARQLsymDifference))
   1.170  		{
   1.171 +			// check required number of arguments
   1.172 +			checkArgs(left, right, third, 2);
   1.173 +			
   1.174  			StrabonPolyhedron rightArg = getValueAsStrabonPolyhedron(right);
   1.175  			return StrabonPolyhedron.symDifference(leftArg, rightArg);
   1.176