package com.dooapp.gaedo.finders.informers;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import com.dooapp.gaedo.finders.FieldInformer;
import com.dooapp.gaedo.finders.FieldInformerAPI;
import com.dooapp.gaedo.finders.QueryExpression;
import com.dooapp.gaedo.finders.expressions.AnythingExpression;
import com.dooapp.gaedo.finders.expressions.EqualsExpression;
import com.dooapp.gaedo.finders.expressions.Expressions;
import com.dooapp.gaedo.finders.expressions.InstanceOfExpression;
import com.dooapp.gaedo.properties.Property;
public class ObjectFieldInformer<InformedType> implements
FieldInformerAPI<InformedType> {
/**
* Field associated to expressions generated by this informer
*/
protected final Property source;
protected Collection<Property> parentPath = Collections.emptyList();
public ObjectFieldInformer(Property source) {
super();
this.source = source;
}
/**
* Refining in accessed type. It is indeed possible to have some subtypes accessed through parent services.
* In such a case, it is useful to be able to restrict on a given type. This expression allows that kind of search.
* Notice operation is equivalent to "this instanceof type" and, as a consequence, is not a strict equals, but
* rather a "classes contains type".
* @param type type we want returned objects to be instances of. it is of course a subtype of this informed type.
* @return an
*/
public QueryExpression instanceOf(Class<? extends InformedType> type) {
return new InstanceOfExpression(source, getFieldPath(), type);
}
/**
* The most common check : is field value equals to input value
*
* @param value
* expected value
* @return a {@link EqualsExpression} checking field value is given value
*/
public QueryExpression equalsTo(Object value) {
return new EqualsExpression(source, getFieldPath(), value);
}
/**
* The second most common check : is field value different from input value
*
* @param value
* expected value
* @return a {@link EqualsExpression} checking field value is given value
* embedded in {@link Expressions#not(QueryExpression)} call
*/
public QueryExpression differentFrom(Object value) {
return Expressions.not(equalsTo(value));
}
/**
* The thirsd most common check : this value is anything. It's a common way to have the field have any value.
* @return
*/
public QueryExpression isAnything() {
return new AnythingExpression(source, getFieldPath());
}
@Override
public String toString() {
StringBuilder sOut = new StringBuilder();
sOut.append(getClass().getName()).append(" on field ").append(source.toGenericString());
return sOut.toString();
}
@Override
public Property getField() {
return source;
}
/**
* @return
* @throws CloneNotSupportedException
* @see java.lang.Object#clone()
*/
@Override
protected ObjectFieldInformer clone() {
return new ObjectFieldInformer(source);
}
@Override
public Iterable<Property> getFieldPath() {
List<Property> returned =new LinkedList<Property>(parentPath);
returned.add(source);
return returned;
}
@Override
public FieldInformer with(Collection<Property> propertyPath) {
ObjectFieldInformer returned = clone();
returned.parentPath = propertyPath;
return returned;
}
/**
* @return
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((source == null) ? 0 : source.hashCode());
return result;
}
/**
* @param obj
* @return
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
ObjectFieldInformer other = (ObjectFieldInformer) obj;
if (source == null) {
if (other.source != null)
return false;
} else if (!source.equals(other.source))
return false;
return true;
}
}