jdbc/src/main/java/org/apache/metamodel/jdbc/dialects/IQueryRewriter.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.metamodel.jdbc.dialects;

import java.sql.Types;

import org.apache.metamodel.jdbc.JdbcDataContext;
import org.apache.metamodel.query.FilterItem;
import org.apache.metamodel.query.FromItem;
import org.apache.metamodel.query.Query;
import org.apache.metamodel.schema.ColumnType;

/**
 * A query rewriter can be used for rewriting (part of) a query's string
 * representation. This is usefull for databases that deviate from the SQL 99
 * compliant syntax which is delievered by the query and it's query item's
 * toString() methods.
 * 
 * @see AbstractQueryRewriter
 * @see JdbcDataContext
 */
public interface IQueryRewriter {

	public String rewriteFromItem(FromItem item);

	public String rewriteQuery(Query query);

	public String rewriteFilterItem(FilterItem whereItem);

	/**
	 * Gets whether this query rewriter is able to write the "Max rows" query
	 * property to the query string.
	 * 
	 * @return whether this query rewriter is able to write the "Max rows" query
	 *         property to the query string.
	 */
	public boolean isMaxRowsSupported();

	/**
	 * Gets whether this query rewriter is able to write the "First row" query
	 * property to the query string.
	 * 
	 * @return whether this query rewriter is able to write the "First row"
	 *         query property to the query string.
	 */
	public boolean isFirstRowSupported();

	/**
	 * Escapes the quotes within a String literal of a query item.
	 * 
	 * @return String item with quotes escaped.
	 */
	public String escapeQuotes(String item);

	/**
	 * Rewrites the name of a column type, as it is written in CREATE TABLE
	 * statements. Some databases dont support all column types, or have
	 * different names for them. The implementation of this method will do that
	 * conversion.
	 * 
	 * @param columnType
	 * @return
	 */
	public String rewriteColumnType(ColumnType columnType);

	/**
	 * Gets the column type for a specific JDBC type (as defined in
	 * {@link Types}), native type name and column size.
	 * 
	 * @param jdbcType
	 * @param nativeType
	 * @param columnSize
	 * @return
	 */
	public ColumnType getColumnType(int jdbcType, String nativeType, Integer columnSize);

}