CustomSql.java

/*
Copyright (c) 2008 Health Market Science, 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.healthmarketscience.sqlbuilder;

import java.io.IOException;

import com.healthmarketscience.common.util.AppendableExt;



/**
 * Outputs the given object as is (can be used to insert any custom SQL into a
 * statement).
 * <p>
 * Example:
 * <pre>
 * String selectQuery =
 *   (new SelectQuery())
 *   .addCustomColumns(new CustomSql("foo"),
 *                     new CustomSql("baz"),
 *                     new CustomSql("buzz"))
 *   .addCustomJoin(SelectQuery.JoinType.INNER_JOIN,
 *                  new CustomSql("table1"), new CustomSql("table2"),
 *                  BinaryCondition.equalTo(
 *                    new CustomSql("table1.id"), new CustomSql("table2.id")))
 *   .addCustomOrderings(new CustomSql("foo"))
 *   .validate().toString();
 *
 * // Output:
 * SELECT foo,baz,buzz FROM table1 INNER JOIN table2 ON (table1.id = table2.id) ORDER BY foo
 * </pre>
 *
 * @see com.healthmarketscience.sqlbuilder.dbspec dbspec database model
 * 
 * @author James Ahlborn
 */
public class CustomSql extends SqlObject
{
  private Object _obj;

  public CustomSql(Object obj) {
    _obj = obj;
  }

  @Override
  protected void collectSchemaObjects(ValidationContext vContext) {
  }
  
  @Override
  public void appendTo(AppendableExt app) throws IOException {
    app.append(_obj);
  }
}