content: package act.db;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2017 ActFramework
   * %%
   * 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.
   * #L%
   */
  
  import act.data.annotation.ParamBindingAnnotation;
  import act.db.di.FindBy;
  import org.osgl.inject.annotation.InjectTag;
  import org.osgl.inject.annotation.LoadValue;
  
  import java.lang.annotation.ElementType;
  import java.lang.annotation.Retention;
  import java.lang.annotation.RetentionPolicy;
  import java.lang.annotation.Target;
  
  /**
   * The annotation specify a field or parameter should be retrieved from
   * database through certain binding key with value get from the current
   * {@link act.util.ActContext}
   */
  @LoadValue(FindBy.class)
  @InjectTag
  @Retention(RetentionPolicy.RUNTIME)
  @Target({ElementType.PARAMETER, ElementType.FIELD})
  @ParamBindingAnnotation
  public @interface DbBind {
      /**
       * Specifies the request parameter name. Default value is an
       * empty string meaning the bind name coming from
       * {@literal @}Named annotation, or field name or param name) will
       * be used as the request parameter name.
       *
       * @return the parameter binding name
       */
      String value() default "";
  
      /**
       * Specify the mapping property name used to query database.
       * Default value is an empty string meaning use the {@link #value() binding name}
       * as the property name.
       *
       * @return the property name used to query the database
       */
      String field() default "";
  
      /**
       * Indicate if it shall use the resolved value to search for ID or normal field
       *
       * **Note** this setting has no effect when any one of the following follow case is `true`
       *
       * 1. the parameter type or field type is collection or iterable
       * 2. {@link #field()} setting is not blank
       *
       * @return `true` if it shall bind by ID field, `false` otherwise
       */
      boolean byId() default true;
  
      /**
       * If {@link #byId()} is `false` then developer can use this field
       * to specify the type of the search field
       * @return the type of the search field
       */
      Class fieldType() default String.class;
  }
  