org.apache.ibatis.builder.annotation.ProviderSqlSource Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of mybatis Show documentation

The MyBatis SQL mapper framework makes it easier to use a relational database with object-oriented applications. MyBatis couples objects with stored procedures or SQL statements using a XML descriptor or annotations. Simplicity is the biggest advantage of the MyBatis data mapper over object relational mapping tools.

There is a newer version: 3.5.16

Show newest version

/*
 *    Copyright 2009-2012 the original author or authors.
 *
 *    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.apache.ibatis.builder.annotation;

import java.lang.reflect.Method;
import java.util.HashMap;

import org.apache.ibatis.builder.BuilderException;
import org.apache.ibatis.builder.SqlSourceBuilder;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.session.Configuration;

/**
 * @author Clinton Begin
 */
public class ProviderSqlSource implements SqlSource {

  private SqlSourceBuilder sqlSourceParser;
  private Class providerType;
  private Method providerMethod;
  private boolean providerTakesParameterObject;

  public ProviderSqlSource(Configuration config, Object provider) {
    String providerMethodName = null;
    try {
      this.sqlSourceParser = new SqlSourceBuilder(config);
      this.providerType = (Class) provider.getClass().getMethod("type").invoke(provider);
      providerMethodName = (String) provider.getClass().getMethod("method").invoke(provider);

      for (Method m : this.providerType.getMethods()) {
        if (providerMethodName.equals(m.getName())) {
          if (m.getParameterTypes().length < 2
              && m.getReturnType() == String.class) {
            this.providerMethod = m;
            this.providerTakesParameterObject = m.getParameterTypes().length == 1;
          }
        }
      }
    } catch (Exception e) {
      throw new BuilderException("Error creating SqlSource for SqlProvider.  Cause: " + e, e);
    }
    if (this.providerMethod == null) {
      throw new BuilderException("Error creating SqlSource for SqlProvider. Method '"
          + providerMethodName + "' not found in SqlProvider '" + this.providerType.getName() + "'.");
    }
  }

  public BoundSql getBoundSql(Object parameterObject) {
    SqlSource sqlSource = createSqlSource(parameterObject);
    return sqlSource.getBoundSql(parameterObject);
  }

  private SqlSource createSqlSource(Object parameterObject) {
    try {
      String sql;
      if (providerTakesParameterObject) {
        sql = (String) providerMethod.invoke(providerType.newInstance(), parameterObject);
      } else {
        sql = (String) providerMethod.invoke(providerType.newInstance());
      }
      Class parameterType = parameterObject == null ? Object.class : parameterObject.getClass();
      return sqlSourceParser.parse(sql, parameterType, new HashMap());
    } catch (Exception e) {
      throw new BuilderException("Error invoking SqlProvider method ("
          + providerType.getName() + "." + providerMethod.getName()
          + ").  Cause: " + e, e);
    }
  }

}