svn-gvsig-desktop / trunk / org.gvsig.desktop / org.gvsig.desktop.library / org.gvsig.expressionevaluator / org.gvsig.expressionevaluator.geometry / org.gvsig.expressionevaluator.geometry.lib / org.gvsig.expressionevaluator.geometry.lib.impl / src / main / java / org / gvsig / expressionevaluator / impl / function / spatial / STStartPointFunction.java @ 44644
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| 1 | 43512 | jjdelcerro | package org.gvsig.expressionevaluator.impl.function.spatial; |
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| 2 | |||
| 3 | import org.apache.commons.lang3.Range; |
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| 4 | 43521 | jjdelcerro | import org.gvsig.expressionevaluator.Interpreter; |
| 5 | 44644 | jjdelcerro | import org.gvsig.expressionevaluator.spi.AbstractGeometryFunction; |
| 6 | 43518 | jjdelcerro | import org.gvsig.fmap.geom.Geometry; |
| 7 | import org.gvsig.fmap.geom.primitive.OrientablePrimitive; |
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| 8 | import org.gvsig.fmap.geom.primitive.Point; |
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| 9 | 43512 | jjdelcerro | |
| 10 | 44644 | jjdelcerro | public class STStartPointFunction extends AbstractGeometryFunction { |
| 11 | 43512 | jjdelcerro | |
| 12 | 43518 | jjdelcerro | public STStartPointFunction() {
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| 13 | super("OGC", "ST_StartPoint", Range.is(1)); |
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| 14 | 43512 | jjdelcerro | } |
| 15 | |||
| 16 | @Override
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| 17 | 44009 | jjdelcerro | public boolean allowConstantFolding() { |
| 18 | return true; |
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| 19 | } |
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| 20 | |||
| 21 | @Override
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| 22 | 43521 | jjdelcerro | public Object call(Interpreter interpreter, Object[] args) throws Exception { |
| 23 | 43518 | jjdelcerro | Geometry geom = getGeom(args, 0);
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| 24 | if ( geom instanceof OrientablePrimitive ) { |
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| 25 | Point n = ((OrientablePrimitive) geom).getVertex(0); |
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| 26 | return n;
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| 27 | } |
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| 28 | return null; |
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| 29 | 43512 | jjdelcerro | } |
| 30 | |||
| 31 | } |