org.opengis.sld
Interface StyleVisitor
@Extension
public interface StyleVisitor
Interface that can be implemented by objects that want to perform some action
on style objects. The visitor design pattern is used to avoid runtime type
checking of objects that descend from a common superclass. So instead of
code that looks like this, with costly instanceof checks:
Symbol s = ... ;
if (s instanceof LineSymbol) {
// Do Line stuff
}
else if (s instanceof PointSymbol) {
// Do Point stuff
}
...
you can implement the SymbolVisitor
interface and the object
itself will invoke the appropriate method:
class MyVisitor implements SymbolVisitor {
public Object visit(LineSymbol symbol, Object userData) {
// Do Line stuff
}
public Object visit(PointSymbol symbol, Object userData) {
// Do Point stuff
}
...
}
...
Symbol s = ... ;
MyVisitor visitor = new MyVisitor(...);
Object o = s.accept(visitor, myData);
- Since:
- GeoAPI 2.0
- Version:
- Implementation specification 1.0
visit
Object visit(LineSymbol symbol,
Object userData)
visit
Object visit(PointSymbol symbol,
Object userData)
visit
Object visit(PolygonSymbol symbol,
Object userData)
visit
Object visit(TextSymbol symbol,
Object userData)
visit
Object visit(ExternalGraphic externalGraphic,
Object userData)
visit
Object visit(Mark mark,
Object userData)
visit
Object visit(LinePlacement placement,
Object userData)
visit
Object visit(PointPlacement placement,
Object userData)
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