com.datastax.driver.mapping.MappedProperty Maven / Gradle / Ivy
/*
* Copyright DataStax, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.datastax.driver.mapping;
import com.datastax.driver.core.TypeCodec;
import com.google.common.reflect.TypeToken;
/**
* A Java property that is mapped to either a table column, a user-defined type (UDT) field, or a
* CQL expression such as {@code "ttl(col1)"}.
*/
public interface MappedProperty {
/**
* Returns this property's name.
*
* @return this property's name; may not be {@code null}.
*/
String getPropertyName();
/**
* Returns the name of the table column or UDT field that this property maps to.
*
* Note that case-sensitive identifiers should be quoted with {@link
* com.datastax.driver.core.Metadata#quote}
*
*
In case of a {@link #isComputed() computed} property, this method should return the CQL
* expression to compute the property value, e.g. {@code "ttl(col1)"}.
*
* @return the name of the table column or UDT field that this property maps to, or the CQL
* expression in case of computed properties; may not be {@code null}.
*/
String getMappedName();
/**
* Returns this property's type.
*
* @return this property's type; may not be {@code null}.
*/
TypeToken getPropertyType();
/**
* Returns the {@link TypeCodec codec} to use to serialize and deserialize this property.
*
* If this method returns {@code null}, then a default codec for the property's {@link
* #getPropertyType() type} will be used.
*
* @return {@link TypeCodec codec} to use to serialize and deserialize this property.
*/
TypeCodec getCustomCodec();
/**
* Returns {@code true} if this property is part of the table's partition key, {@code false}
* otherwise.
*
* This method has no effect if this property is mapped to a UDT field or a CQL expression.
*
* @return {@code true} if this property is part of the table's partition key, {@code false}
* otherwise.
* @see com.datastax.driver.mapping.annotations.PartitionKey
*/
boolean isPartitionKey();
/**
* Returns {@code true} if this property is a clustering column, {@code false} otherwise.
*
*
This method has no effect if this property is mapped to a UDT field or a CQL expression.
*
* @return {@code true} if this property is a clustering column, {@code false} otherwise.
* @see com.datastax.driver.mapping.annotations.ClusteringColumn
*/
boolean isClusteringColumn();
/**
* Returns this property's zero-based position among partition key columns or clustering columns.
*
*
For example, assuming the following primary key definition: {@code PRIMARY KEY ((col1,
* col2), col3, col4)}, {@code col1} has position 0 (i.e. first partition key column), {@code
* col2} has position 1 (i.e. second partition key column), {@code col3} has position 0 (i.e.
* first clustering key column), {@code col4} has position 1 (i.e. second clustering key column),
*
*
This method has no effect if this property is not part of the primary key, or if it is
* mapped to a UDT field or a CQL expression. Implementors are encouraged to return {@code -1} in
* these situations.
*
* @return this property's zero-based position among partition key columns or clustering columns.
*/
int getPosition();
/**
* Returns {@code true} if this property is computed, i.e. if it represents the result of a CQL
* expression such as {@code "ttl(col1)"}, {@code false} otherwise.
*
*
Computed properties are not allowed with protocol v1.
*
*
Also note that computed properties are read-only.
*
* @return {@code true} if this property is computed, {@code false} otherwise.
* @see com.datastax.driver.mapping.annotations.Computed
*/
boolean isComputed();
/**
* Reads the current value of this property in the given {@code entity}.
*
* @param entity The instance to read the property from; may not be {@code null}.
* @return The property value.
* @throws IllegalArgumentException if the property cannot be read.
*/
T getValue(Object entity);
/**
* Writes the given value to this property in the given {@code entity}.
*
* @param entity The instance to write the property to; may not be {@code null}.
* @param value The property value.
* @throws IllegalArgumentException if the property cannot be written.
*/
void setValue(Object entity, T value);
}