iciql/src/main/java/com/iciql/SQLDialectSQLite.java

/*
 * Copyright 2014 James Moger.
 *
 * 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.iciql;

import java.sql.Date;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Time;
import java.sql.Timestamp;

import com.iciql.Iciql.DataTypeAdapter;
import com.iciql.TableDefinition.FieldDefinition;
import com.iciql.TableDefinition.IndexDefinition;
import com.iciql.util.IciqlLogger;
import com.iciql.util.StatementBuilder;


/**
 * SQLite database dialect.
 */
public class SQLDialectSQLite extends SQLDialectDefault {

	@Override
	public boolean supportsSavePoints() {
		// SAVEPOINT support was added after the 3.8.7 release
		String [] chunks = productVersion.split("\\.");
		if (Integer.parseInt(chunks[0]) > 3) {
			return true;
		}
		float f = Float.parseFloat(chunks[1] + "." + chunks[2]);
		return (f > 8.7);
	}

	@Override
	protected <T> String prepareCreateTable(TableDefinition<T> def) {
		return "CREATE TABLE IF NOT EXISTS";
	}

	@Override
	protected <T> String prepareCreateView(TableDefinition<T> def) {
		return "CREATE VIEW IF NOT EXISTS";
	}

	@Override
	public String convertSqlType(String sqlType) {
		if (isIntegerType(sqlType)) {
			return "INTEGER";
		}
		return sqlType;
	}

	@Override
	protected boolean prepareColumnDefinition(StatementBuilder buff, String dataType,
			boolean isAutoIncrement, boolean isPrimaryKey) {
		String convertedType = convertSqlType(dataType);
		buff.append(convertedType);
		if (isPrimaryKey) {
			buff.append(" PRIMARY KEY");
			if (isAutoIncrement) {
				buff.append(" AUTOINCREMENT");
			}
			return true;
		}
		return false;
	}

	@Override
	public <T> void prepareDropView(SQLStatement stat, TableDefinition<T> def) {
		StatementBuilder buff = new StatementBuilder("DROP VIEW IF EXISTS "
				+ prepareTableName(def.schemaName, def.tableName));
		stat.setSQL(buff.toString());
		return;
	}

	@Override
	public void prepareCreateIndex(SQLStatement stat, String schemaName, String tableName,
			IndexDefinition index) {
		StatementBuilder buff = new StatementBuilder();
		buff.append("CREATE ");
		switch (index.type) {
		case UNIQUE:
			buff.append("UNIQUE ");
			break;
		case UNIQUE_HASH:
			buff.append("UNIQUE ");
			break;
		default:
			IciqlLogger.warn("{0} does not support hash indexes", getClass().getSimpleName());
		}
		buff.append("INDEX IF NOT EXISTS ");
		buff.append(index.indexName);
		buff.append(" ON ");
		buff.append(tableName);
		buff.append("(");
		for (String col : index.columnNames) {
			buff.appendExceptFirst(", ");
			buff.append(prepareColumnName(col));
		}
		buff.append(") ");

		stat.setSQL(buff.toString().trim());
	}

	@Override
	public <T> void prepareMerge(SQLStatement stat, String schemaName, String tableName,
			TableDefinition<T> def, Object obj) {
		StatementBuilder buff = new StatementBuilder("INSERT OR REPLACE INTO ");
		buff.append(prepareTableName(schemaName, tableName)).append(" (");
		buff.resetCount();
		for (FieldDefinition field : def.fields) {
			buff.appendExceptFirst(", ");
			buff.append(field.columnName);
		}
		buff.append(") ");
		buff.resetCount();
		buff.append("VALUES (");
		for (FieldDefinition field : def.fields) {
			buff.appendExceptFirst(", ");
			buff.append('?');
			Object value = def.getValue(obj, field);
			Object parameter = serialize(value, field.typeAdapter);
			stat.addParameter(parameter);
		}
		buff.append(')');
		stat.setSQL(buff.toString());
	}

	@Override
	public Object deserialize(ResultSet rs, int columnIndex, Class<?> targetType, Class<? extends DataTypeAdapter<?>> typeAdapter) {
		try {
			return super.deserialize(rs, columnIndex, targetType, typeAdapter);
		} catch (IciqlException e) {
			if (typeAdapter == null && e.getMessage().startsWith("Can not convert")) {
				try {
					// give the SQLite JDBC driver an opportunity to deserialize DateTime objects
					if (Timestamp.class.equals(targetType)) {
						return rs.getTimestamp(columnIndex);
					} else if (Time.class.equals(targetType)) {
						return rs.getTime(columnIndex);
					} else if (Date.class.equals(targetType)) {
						return rs.getDate(columnIndex);
					} else if (java.util.Date.class.equals(targetType)) {
						Timestamp timestamp = rs.getTimestamp(columnIndex);
						return new java.util.Date(timestamp.getTime());
					}
				} catch (SQLException x) {
					throw new IciqlException(x, "Can not convert the value at column {0} to {1}",
							columnIndex, targetType.getName());
				}
			}

			// rethrow e
			throw e;
		}
	}

	@Override
	public String prepareStringParameter(Object o) {
		if (o instanceof Boolean) {
			// SQLite does not have an explicit BOOLEAN type
			Boolean bool = (Boolean) o;
			return bool ? "1" : "0";
		}
		return super.prepareStringParameter(o);
	}
}