/*
* 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.facebook.presto.spi.session;
import com.facebook.presto.spi.type.Type;
import java.util.function.Function;
import static com.facebook.presto.spi.type.BigintType.BIGINT;
import static com.facebook.presto.spi.type.BooleanType.BOOLEAN;
import static com.facebook.presto.spi.type.DoubleType.DOUBLE;
import static com.facebook.presto.spi.type.IntegerType.INTEGER;
import static com.facebook.presto.spi.type.VarcharType.VARCHAR;
import static java.util.Locale.ENGLISH;
import static java.util.Objects.requireNonNull;
public final class PropertyMetadata<T>
{
private final String name;
private final String description;
private final Type sqlType;
private final Class<T> javaType;
private final T defaultValue;
private final boolean hidden;
private final Function<Object, T> decoder;
private final Function<T, Object> encoder;
public PropertyMetadata(
String name,
String description,
Type sqlType,
Class<T> javaType,
T defaultValue,
boolean hidden,
Function<Object, T> decoder,
Function<T, Object> encoder)
{
requireNonNull(name, "name is null");
requireNonNull(description, "description is null");
requireNonNull(sqlType, "type is null");
requireNonNull(javaType, "javaType is null");
requireNonNull(decoder, "decoder is null");
requireNonNull(encoder, "encoder is null");
if (name.isEmpty() || !name.trim().toLowerCase(ENGLISH).equals(name)) {
throw new IllegalArgumentException(String.format("Invalid session property name '%s'", name));
}
if (description.isEmpty() || !description.trim().equals(description)) {
throw new IllegalArgumentException(String.format("Invalid session property description '%s'", description));
}
this.name = name;
this.description = description;
this.javaType = javaType;
this.sqlType = sqlType;
this.defaultValue = defaultValue;
this.hidden = hidden;
this.decoder = decoder;
this.encoder = encoder;
}
/**
* Name of the session property. This must be a valid identifier.
*/
public String getName()
{
return name;
}
/**
* Description for the end user.
*/
public String getDescription()
{
return description;
}
/**
* SQL type of the property.
*/
public Type getSqlType()
{
return sqlType;
}
/**
* Java type of this property.
*/
public Class<T> getJavaType()
{
return javaType;
}
/**
* Gets the default value for this property.
*/
public T getDefaultValue()
{
return defaultValue;
}
/**
* Is this property hidden from users?
*/
public boolean isHidden()
{
return hidden;
}
/**
* Decodes the SQL type object value to the Java type of the property.
*/
public T decode(Object value)
{
return decoder.apply(value);
}
/**
* Encodes the Java type value to SQL type object value
*/
public Object encode(T value)
{
return encoder.apply(value);
}
public static <T> PropertyMetadata<Boolean> booleanSessionProperty(String name, String description, Boolean defaultValue, boolean hidden)
{
return new PropertyMetadata<>(
name,
description,
BOOLEAN,
Boolean.class,
defaultValue,
hidden,
Boolean.class::cast,
object -> object);
}
public static PropertyMetadata<Integer> integerSessionProperty(String name, String description, Integer defaultValue, boolean hidden)
{
return new PropertyMetadata<>(
name,
description,
INTEGER,
Integer.class,
defaultValue,
hidden,
value -> ((Number) value).intValue(),
object -> object);
}
public static PropertyMetadata<Long> longSessionProperty(String name, String description, Long defaultValue, boolean hidden)
{
return new PropertyMetadata<>(
name,
description,
BIGINT,
Long.class,
defaultValue,
hidden,
value -> ((Number) value).longValue(),
object -> object);
}
public static PropertyMetadata<Double> doubleSessionProperty(String name, String description, Double defaultValue, boolean hidden)
{
return new PropertyMetadata<>(
name,
description,
DOUBLE,
Double.class,
defaultValue,
hidden,
value -> ((Number) value).doubleValue(),
object -> object);
}
public static PropertyMetadata<String> stringSessionProperty(String name, String description, String defaultValue, boolean hidden)
{
return new PropertyMetadata<>(
name,
description,
VARCHAR,
String.class,
defaultValue,
hidden,
String.class::cast,
object -> object);
}
}