org.jdbi.v3.sqlobject.config.internal.UseSqlParserImpl Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of jdbi3-sqlobject Show documentation

SqlObject is a declarative, annotation-driven API for database access. It complements the core API. Jdbi 3 is designed to provide convenient tabular data access in Java(tm) and other JVM based languages. It uses the Java collections framework for query results, provides a convenient means of externalizing SQL statements, and named parameter support for any database that supports JDBC.

There is a newer version: 3.47.0

Show newest version

/*
 * 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 org.jdbi.v3.sqlobject.config.internal;

import java.lang.annotation.Annotation;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.Objects;
import java.util.function.Supplier;
import java.util.stream.Stream;

import javax.annotation.Nullable;

import org.jdbi.v3.core.config.ConfigRegistry;
import org.jdbi.v3.core.internal.exceptions.Unchecked;
import org.jdbi.v3.core.statement.SqlParser;
import org.jdbi.v3.core.statement.SqlStatements;
import org.jdbi.v3.sqlobject.config.Configurer;
import org.jdbi.v3.sqlobject.config.UseSqlParser;

public class UseSqlParserImpl implements Configurer {
    @Override
    public void configureForMethod(ConfigRegistry registry, Annotation annotation, Class sqlObjectType, Method method) {
        UseSqlParser anno = (UseSqlParser) annotation;
        SqlParser parser = instantiate(anno.value(), sqlObjectType, method);
        registry.get(SqlStatements.class).setSqlParser(parser);
    }

    @Override
    public void configureForType(ConfigRegistry registry, Annotation annotation, Class sqlObjectType) {
        configureForMethod(registry, annotation, sqlObjectType, null);
    }

    private SqlParser instantiate(Class parserClass,
                                  Class sqlObjectType,
                                  @Nullable Method method) {
        return Stream.of(tryConstructor(parserClass), tryConstructor(parserClass, sqlObjectType), tryConstructor(parserClass, sqlObjectType, method))
            .map(Supplier::get)
            .filter(Objects::nonNull)
            .findFirst()
            .orElseThrow(() -> new IllegalStateException("Unable to instantiate, no viable constructor for " + parserClass.getName()));
    }

    private static  Supplier tryConstructor(Class clazz, Object... args) {
        return Unchecked.supplier(() -> {
            try {
                Object[] nonNullArgs = Arrays.stream(args).filter(Objects::nonNull).toArray(Object[]::new);
                Class[] argClasses = Arrays.stream(nonNullArgs).map(Object::getClass).toArray(Class[]::new);
                MethodType type = MethodType.methodType(void.class, argClasses);
                return clazz.cast(MethodHandles.lookup()
                        .findConstructor(clazz, type)
                        .invokeWithArguments(nonNullArgs));
            } catch (NoSuchMethodException ignored) {
                return null;
            }
        });
    }
}