Added some documentation to the spatial.query package. Some reformatting too.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1356561 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
David Wayne Smiley 2012-07-03 03:19:03 +00:00
parent fccd1be5e7
commit 0963bc09b3
3 changed files with 54 additions and 32 deletions

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@ -23,6 +23,8 @@ import com.spatial4j.core.exception.InvalidSpatialArgument;
import com.spatial4j.core.shape.Shape; import com.spatial4j.core.shape.Shape;
/** /**
* Principally holds the query {@link Shape} and the {@link SpatialOperation}.
*
* @lucene.experimental * @lucene.experimental
*/ */
public class SpatialArgs { public class SpatialArgs {
@ -46,34 +48,31 @@ public class SpatialArgs {
this.shape = shape; this.shape = shape;
} }
/** /** Check if the arguments make sense -- throw an exception if not */
* Check if the arguments make sense -- throw an exception if not
*/
public void validate() throws InvalidSpatialArgument { public void validate() throws InvalidSpatialArgument {
if (operation.isTargetNeedsArea() && !shape.hasArea()) { if (operation.isTargetNeedsArea() && !shape.hasArea()) {
throw new InvalidSpatialArgument(operation + " only supports geometry with area"); throw new InvalidSpatialArgument(operation + " only supports geometry with area");
} }
} }
public String toString( SpatialContext context ) { public String toString(SpatialContext context) {
StringBuilder str = new StringBuilder(); StringBuilder str = new StringBuilder();
str.append( operation.getName() ).append( '(' ); str.append(operation.getName()).append('(');
str.append( context.toString( shape ) ); str.append(context.toString(shape));
if( min != null ) { if (min != null) {
str.append(" min=").append(min); str.append(" min=").append(min);
} }
if( max != null ) { if (max != null) {
str.append(" max=").append(max); str.append(" max=").append(max);
} }
str.append(" distPrec=").append(String.format("%.2f%%", distPrecision/100d)); str.append(" distPrec=").append(String.format("%.2f%%", distPrecision / 100d));
str.append( ')' ); str.append(')');
return str.toString(); return str.toString();
} }
@Override @Override
public String toString() public String toString() {
{ return toString(SimpleSpatialContext.GEO_KM);
return toString( SimpleSpatialContext.GEO_KM );
} }
//------------------------------------------------ //------------------------------------------------
@ -88,9 +87,7 @@ public class SpatialArgs {
this.operation = operation; this.operation = operation;
} }
/** /** Considers {@link SpatialOperation#BBoxWithin} in returning the shape. */
* Considers {@link SpatialOperation#BBoxWithin} in returning the shape.
*/
public Shape getShape() { public Shape getShape() {
if (shape != null && (operation == SpatialOperation.BBoxWithin || operation == SpatialOperation.BBoxIntersects)) if (shape != null && (operation == SpatialOperation.BBoxWithin || operation == SpatialOperation.BBoxIntersects))
return shape.getBoundingBox(); return shape.getBoundingBox();
@ -102,9 +99,10 @@ public class SpatialArgs {
} }
/** /**
* The fraction of the distance from the center of the query shape to its nearest edge that is considered acceptable * The fraction of the distance from the center of the query shape to its nearest edge
* error. The algorithm for computing the distance to the nearest edge is actually a little different. It normalizes * that is considered acceptable error. The algorithm for computing the distance to the
* the shape to a square given it's bounding box area: * nearest edge is actually a little different. It normalizes the shape to a square
* given it's bounding box area:
* <pre>sqrt(shape.bbox.area)/2</pre> * <pre>sqrt(shape.bbox.area)/2</pre>
* And the error distance is beyond the shape such that the shape is a minimum shape. * And the error distance is beyond the shape such that the shape is a minimum shape.
*/ */

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@ -27,10 +27,32 @@ import java.util.Map;
import java.util.StringTokenizer; import java.util.StringTokenizer;
/** /**
* Parses a string that usually looks like "OPERATION(SHAPE)" into a {@link SpatialArgs}
* object. The set of operations supported are defined in {@link SpatialOperation}, such
* as "Intersects" being a common one. The shape portion is defined by {@link
* SpatialContext#readShape(String)}. There are some optional name-value pair parameters
* that follow the closing parenthesis. Example:
* <pre>
* Intersects(-10,20,-8,22) distPec=0.025
* </pre>
* <p/>
* In the future it would be good to support something at least semi-standardized like a
* variant of <a href="http://docs.geoserver.org/latest/en/user/filter/ecql_reference.html#spatial-predicate">
* [E]CQL</a>.
*
* @lucene.experimental * @lucene.experimental
*/ */
public class SpatialArgsParser public class SpatialArgsParser {
{
/**
* Parses a string such as "Intersects(-10,20,-8,22) distPec=0.025".
*
* @param v The string to parse. Mandatory.
* @param ctx The spatial context. Mandatory.
* @return Not null.
* @throws InvalidSpatialArgument If there is a problem parsing the string.
* @throws InvalidShapeException Thrown from {@link SpatialContext#readShape(String)}
*/
public SpatialArgs parse(String v, SpatialContext ctx) throws InvalidSpatialArgument, InvalidShapeException { public SpatialArgs parse(String v, SpatialContext ctx) throws InvalidSpatialArgument, InvalidShapeException {
int idx = v.indexOf('('); int idx = v.indexOf('(');
int edx = v.lastIndexOf(')'); int edx = v.lastIndexOf(')');
@ -47,13 +69,13 @@ public class SpatialArgsParser
} }
Shape shape = ctx.readShape(body); Shape shape = ctx.readShape(body);
SpatialArgs args = new SpatialArgs(op,shape); SpatialArgs args = new SpatialArgs(op, shape);
if (v.length() > (edx + 1)) { if (v.length() > (edx + 1)) {
body = v.substring( edx+1 ).trim(); body = v.substring(edx + 1).trim();
if (body.length() > 0) { if (body.length() > 0) {
Map<String,String> aa = parseMap(body); Map<String, String> aa = parseMap(body);
args.setMin(readDouble(aa.remove("min")) ); args.setMin(readDouble(aa.remove("min")));
args.setMax(readDouble(aa.remove("max"))); args.setMax(readDouble(aa.remove("max")));
args.setDistPrecision(readDouble(aa.remove("distPrec"))); args.setDistPrecision(readDouble(aa.remove("distPrec")));
if (!aa.isEmpty()) { if (!aa.isEmpty()) {
@ -65,15 +87,15 @@ public class SpatialArgsParser
} }
protected static Double readDouble(String v) { protected static Double readDouble(String v) {
return v == null ? null : Double.valueOf(v); return v == null ? null : Double.valueOf(v);
} }
protected static boolean readBool(String v, boolean defaultValue) { protected static boolean readBool(String v, boolean defaultValue) {
return v == null ? defaultValue : Boolean.parseBoolean(v); return v == null ? defaultValue : Boolean.parseBoolean(v);
} }
protected static Map<String,String> parseMap(String body) { protected static Map<String, String> parseMap(String body) {
Map<String,String> map = new HashMap<String,String>(); Map<String, String> map = new HashMap<String, String>();
StringTokenizer st = new StringTokenizer(body, " \n\t"); StringTokenizer st = new StringTokenizer(body, " \n\t");
while (st.hasMoreTokens()) { while (st.hasMoreTokens()) {
String a = st.nextToken(); String a = st.nextToken();

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@ -20,15 +20,17 @@ package org.apache.lucene.spatial.query;
import com.spatial4j.core.exception.InvalidSpatialArgument; import com.spatial4j.core.exception.InvalidSpatialArgument;
import java.io.Serializable; import java.io.Serializable;
import java.util.*; import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
/** /**
* A clause that compares a stored geometry to a supplied geometry. * A clause that compares a stored geometry to a supplied geometry.
* *
* @see <a href="http://edndoc.esri.com/arcsde/9.1/general_topics/understand_spatial_relations.htm"> * @see <a href="http://edndoc.esri.com/arcsde/9.1/general_topics/understand_spatial_relations.htm">
* ESRIs docs on spatial relations</a> * ESRIs docs on spatial relations</a>
* @see <a href="http://docs.geoserver.org/latest/en/user/filter/ecql_reference.html#spatial-predicate">
* GeoServer ECQL Spatial Predicates</a>
* *
* @lucene.experimental * @lucene.experimental
*/ */