package er.cayenne.example;
import java.util.ArrayList;
import java.util.List;
import org.apache.cayenne.exp.Expression;
import org.apache.cayenne.exp.ExpressionFactory;
import org.apache.cayenne.query.SortOrder;
import er.cayenne.example.ChainableOrdering.ChainableOrderings;
/**
* A key in a DataObject.
*
* @param <E> The type this key returns.
*/
public class Key<E> {
/**
* Name of the key in the object
*/
private String _key;
/**
* Constructs a new key with the given name.
*/
public Key( String key ) {
_key = key;
}
/**
* @return Name of the key in the object.
*/
public String key() {
return _key;
}
/**
* @return An expression representing null.
*/
public Expression isNull() {
return ExpressionFactory.matchExp( key(), null );
}
/**
* @return An expression representing a non-null value.
*/
public Expression isNotNull() {
return ExpressionFactory.matchExp( key(), null ).notExp();
}
/**
* @return An expression representing equality.
*/
public Expression eq( E value ) {
return ExpressionFactory.matchExp( key(), value );
}
/**
* @return An expression representing inequality.
*/
public Expression ne( E value ) {
return ExpressionFactory.noMatchExp( key(), value );
}
/**
* @return An expression for a Database "Like" query.
*/
public Expression like( E value ) {
return ExpressionFactory.likeExp( key(), value );
}
/**
* @return An expression for a case insensitive "Like" query.
*/
public Expression likeInsensitive( E value ) {
return ExpressionFactory.likeIgnoreCaseExp( key(), value );
}
/**
* @return An expression applying to objects between the two given bounds (not inclusive)
*
* @param lower The lower bound. [null] represents infinity.
* @param upper The upper bound. [null] represents infinity.
*/
public Expression between( E lower, E upper ) {
return between( lower, upper, false );
}
/**
* @return An expression applying to objects between the two given bounds (not inclusive)
*
* @param lower The lower bound. [null] represents infinity.
* @param upper The upper bound. [null] represents infinity.
*/
public Expression between( E lower, E upper, boolean inclusive ) {
List<Expression> expressions = new ArrayList<Expression>();
if( lower != null ) {
if( inclusive ) {
expressions.add( gte( lower ) );
}
else {
expressions.add( gt( lower ) );
}
}
if( upper != null ) {
if( inclusive ) {
expressions.add( lte( upper ) );
}
else {
expressions.add( lt( upper ) );
}
}
return andExpressions( expressions );
}
/**
* @return An expression for finding objects with values in the given set.
*/
public Expression in( E ... values ) {
return ExpressionFactory.inExp( key(), values );
}
/**
* @return A greater than Expression.
*/
public Expression gt( E value ) {
return ExpressionFactory.greaterExp( key(), value );
}
/**
* @return A greater than or equal to Expression.
*/
public Expression gte( E value ) {
return ExpressionFactory.greaterOrEqualExp( key(), value );
}
/**
* @return A less than Expression.
*/
public Expression lt( E value) {
return ExpressionFactory.lessExp( key(), value );
}
/**
* @return A less than or equal to Expression.
*/
public Expression lte( E value) {
return ExpressionFactory.lessOrEqualExp( key(), value );
}
/**
* @return Ascending sort orderings on this key.
*/
public ChainableOrdering asc() {
return new ChainableOrdering( key(), SortOrder.ASCENDING );
}
/**
* @return Ascending sort orderings on this key.
*/
public ChainableOrderings ascs() {
return new ChainableOrderings( asc() );
}
/**
* @return Ascending case insensitive sort orderings on this key.
*/
public ChainableOrdering ascInsensitive() {
return new ChainableOrdering( key(), SortOrder.ASCENDING_INSENSITIVE );
}
/**
* @return Ascending case insensitive sort orderings on this key.
*/
public ChainableOrderings ascInsensitives() {
return new ChainableOrderings( ascInsensitive() );
}
/**
* @return Descending sort orderings on this key.
*/
public ChainableOrdering desc() {
return new ChainableOrdering( key(), SortOrder.DESCENDING );
}
/**
* @return Descending sort orderings on this key.
*/
public ChainableOrderings descs() {
return new ChainableOrderings(desc() );
}
/**
* @return Descending case insensitive sort orderings on this key.
*/
public ChainableOrdering descInsensitive() {
return new ChainableOrdering( key(), SortOrder.DESCENDING_INSENSITIVE );
}
/**
* @return Descending case insensitive sort orderings on this key.
*/
public ChainableOrderings descInsensitives() {
return new ChainableOrderings( descInsensitive() );
}
/**
* @return An expression with the given expressions combined with logical "and".
*/
private static Expression andExpressions( List<Expression> expressions ) {
Expression resultExpression = null;
for( Expression e : expressions ) {
if( resultExpression == null ) {
resultExpression = e;
}
else {
resultExpression = resultExpression.andExp( e );
}
}
return resultExpression;
}
public String dot( String key ) {
return key() + "." + key;
}
public String dot( Key<?> key ) {
return key() + "." + key.key();
}
}