Java tutorial
/* * 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.openjpa.jdbc.sql; import java.sql.Connection; import java.sql.DatabaseMetaData; import java.sql.SQLException; import java.sql.Types; import java.util.Arrays; import java.util.Locale; import org.apache.commons.lang.StringUtils; import org.apache.openjpa.jdbc.identifier.DBIdentifier; import org.apache.openjpa.jdbc.kernel.exps.FilterValue; import org.apache.openjpa.jdbc.schema.Column; import org.apache.openjpa.jdbc.schema.PrimaryKey; import org.apache.openjpa.jdbc.schema.Table; import org.apache.openjpa.jdbc.schema.Unique; import org.apache.openjpa.meta.JavaTypes; import org.apache.openjpa.util.StoreException; /** * Dictionary for H2 ({@link http://www.h2database.com}). * * @since 0.9.7 */ public class H2Dictionary extends DBDictionary { public H2Dictionary() { platform = "H2"; validationSQL = "CALL 1"; closePoolSQL = "SHUTDOWN"; supportsAutoAssign = true; lastGeneratedKeyQuery = "CALL IDENTITY()"; autoAssignClause = "IDENTITY"; autoAssignTypeName = "INTEGER"; nextSequenceQuery = "CALL NEXT VALUE FOR {0}"; stringLengthFunction = "LENGTH({0})"; trimLeadingFunction = "LTRIM({0})"; trimTrailingFunction = "RTRIM({0})"; trimBothFunction = "TRIM({0})"; supportsSelectStartIndex = true; supportsSelectEndIndex = true; rangePosition = RANGE_POST_LOCK; supportsDeferredConstraints = false; supportsNullTableForGetPrimaryKeys = true; supportsNullTableForGetIndexInfo = true; supportsLockingWithOuterJoin = false; supportsLockingWithInnerJoin = false; reservedWordSet.addAll(Arrays.asList(new String[] { "CURRENT_TIMESTAMP", "CURRENT_TIME", "CURRENT_DATE", "CROSS", "DISTINCT", "EXCEPT", "EXISTS", "FROM", "FOR", "FALSE", "FULL", "GROUP", "HAVING", "INNER", "INTERSECT", "IS", "JOIN", "LIKE", "MINUS", "NATURAL", "NOT", "NULL", "ON", "ORDER", "PRIMARY", "ROWNUM", "SELECT", "SYSDATE", "SYSTIME", "SYSTIMESTAMP", "TODAY", "TRUE", "UNION", "WHERE" })); // reservedWordSet subset that CANNOT be used as valid column names // (i.e., without surrounding them with double-quotes) invalidColumnWordSet.addAll(Arrays.asList(new String[] { "ORDER", })); } @Override public int getJDBCType(int metaTypeCode, boolean lob) { int type = super.getJDBCType(metaTypeCode, lob); switch (type) { case Types.BIGINT: if (metaTypeCode == JavaTypes.BIGINTEGER) return Types.NUMERIC; break; } return type; } @Override public int getPreferredType(int type) { if (type == Types.BIT) return Types.BOOLEAN; return type; } @Override public String[] getAddPrimaryKeySQL(PrimaryKey pk) { return new String[0]; } @Override public String[] getDropPrimaryKeySQL(PrimaryKey pk) { return new String[0]; } @Override public String[] getAddColumnSQL(Column column) { return new String[] { "ALTER TABLE " + getFullName(column.getTable(), false) + " ADD COLUMN " + getDeclareColumnSQL(column, true) }; } @Override public String[] getCreateTableSQL(Table table) { StringBuilder buf = new StringBuilder(); buf.append("CREATE TABLE ").append(getFullName(table, false)).append(" ("); Column[] cols = table.getColumns(); for (int i = 0; i < cols.length; i++) { if (i > 0) buf.append(", "); buf.append(getDeclareColumnSQL(cols[i], false)); } PrimaryKey pk = table.getPrimaryKey(); String pkStr; if (pk != null) { pkStr = getPrimaryKeyConstraintSQL(pk); if (!StringUtils.isEmpty(pkStr)) buf.append(", ").append(pkStr); } Unique[] unqs = table.getUniques(); String unqStr; for (int i = 0; i < unqs.length; i++) { unqStr = getUniqueConstraintSQL(unqs[i]); if (unqStr != null) buf.append(", ").append(unqStr); } buf.append(")"); return new String[] { buf.toString() }; } @Override protected String getPrimaryKeyConstraintSQL(PrimaryKey pk) { Column[] cols = pk.getColumns(); if (cols.length == 1 && cols[0].isAutoAssigned()) return null; return super.getPrimaryKeyConstraintSQL(pk); } public boolean isSystemIndex(String name, Table table) { return name.toUpperCase(Locale.ENGLISH).startsWith("SYSTEM_"); } public boolean isSystemIndex(DBIdentifier name, Table table) { if (DBIdentifier.isNull(name)) { return false; } return name.getName().toUpperCase(Locale.ENGLISH).startsWith("SYSTEM_"); } @Override protected String getSequencesSQL(String schemaName, String sequenceName) { return getSequencesSQL(DBIdentifier.newSchema(schemaName), DBIdentifier.newSequence(sequenceName)); } @Override protected String getSequencesSQL(DBIdentifier schemaName, DBIdentifier sequenceName) { StringBuilder buf = new StringBuilder(); buf.append("SELECT SEQUENCE_SCHEMA, SEQUENCE_NAME FROM ").append("INFORMATION_SCHEMA.SEQUENCES"); if (!DBIdentifier.isNull(schemaName) || !DBIdentifier.isNull(sequenceName)) buf.append(" WHERE "); if (!DBIdentifier.isNull(schemaName)) { buf.append("SEQUENCE_SCHEMA = ?"); if (!DBIdentifier.isNull(sequenceName)) buf.append(" AND "); } if (!DBIdentifier.isNull(sequenceName)) buf.append("SEQUENCE_NAME = ?"); return buf.toString(); } @Override public Column[] getColumns(DatabaseMetaData meta, String catalog, String schemaName, String tableName, String columnName, Connection conn) throws SQLException { return getColumns(meta, DBIdentifier.newCatalog(catalog), DBIdentifier.newSchema(schemaName), DBIdentifier.newTable(tableName), DBIdentifier.newColumn(columnName), conn); } @Override public Column[] getColumns(DatabaseMetaData meta, DBIdentifier catalog, DBIdentifier schemaName, DBIdentifier tableName, DBIdentifier columnName, Connection conn) throws SQLException { Column[] cols = super.getColumns(meta, catalog, schemaName, tableName, columnName, conn); return cols; } @Override protected void appendSelectRange(SQLBuffer buf, long start, long end, boolean subselect) { if (end != Long.MAX_VALUE) buf.append(" LIMIT ").appendValue(end - start); if (start != 0) { if (end == Long.MAX_VALUE) buf.append(" LIMIT 0"); buf.append(" OFFSET ").appendValue(start); } } @Override public void indexOf(SQLBuffer buf, FilterValue str, FilterValue find, FilterValue start) { buf.append("LOCATE("); find.appendTo(buf); buf.append(", "); str.appendTo(buf); if (start != null) { buf.append(", "); start.appendTo(buf); } buf.append(")"); } @Override public boolean isFatalException(int subtype, SQLException ex) { int errorCode = ex.getErrorCode(); if ((subtype == StoreException.QUERY || subtype == StoreException.LOCK) && (57014 == errorCode || 50200 == errorCode)) { return false; } return super.isFatalException(subtype, ex); } }