Mercurial > hg > release > thermostat-0.11
view storage/core/src/main/java/com/redhat/thermostat/storage/internal/statement/ParsedStatement.java @ 1152:4ba43dcff78e
Implement prepared statements (Part 1).
Reviewed-by: ebaron
Review-thread: http://icedtea.classpath.org/pipermail/thermostat/2013-June/007214.html
author | Severin Gehwolf <sgehwolf@redhat.com> |
---|---|
date | Fri, 28 Jun 2013 15:27:50 +0200 |
parents | |
children |
line wrap: on
line source
/* * Copyright 2012, 2013 Red Hat, Inc. * * This file is part of Thermostat. * * Thermostat is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation; either version 2, or (at your * option) any later version. * * Thermostat is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Thermostat; see the file COPYING. If not see * <http://www.gnu.org/licenses/>. * * Linking this code with other modules is making a combined work * based on this code. Thus, the terms and conditions of the GNU * General Public License cover the whole combination. * * As a special exception, the copyright holders of this code give * you permission to link this code with independent modules to * produce an executable, regardless of the license terms of these * independent modules, and to copy and distribute the resulting * executable under terms of your choice, provided that you also * meet, for each linked independent module, the terms and conditions * of the license of that module. An independent module is a module * which is not derived from or based on this code. If you modify * this code, you may extend this exception to your version of the * library, but you are not obligated to do so. If you do not wish * to do so, delete this exception statement from your version. */ package com.redhat.thermostat.storage.internal.statement; import com.redhat.thermostat.storage.core.Query; import com.redhat.thermostat.storage.core.Statement; import com.redhat.thermostat.storage.query.Expression; /** * Result object as returned by {@link StatementDescriptorParser#parse()}. * An instance of this plus an {@link PreparedStatementImpl} instance should * be sufficient to patch up a prepared statement with its real values. * * @see PreparedStatementImpl#executeQuery() */ class ParsedStatement { private int numParams; private SuffixExpression suffixExpn; private final Statement statement; ParsedStatement(Statement statement) { this.statement = statement; } public int getNumParams() { return numParams; } public Statement getRawStatement() { return statement; } public Statement patchQuery(PreparedStatementImpl stmt) throws IllegalPatchException { if (suffixExpn == null) { String msg = "Suffix expression must be set before patching!"; IllegalStateException expn = new IllegalStateException(msg); throw new IllegalPatchException(expn); } PreparedParameter[] params = stmt.getParams(); patchWhere(params); patchSort(params); patchLimit(params); // TODO count actual patches and throw an exception if not all vars // have been patched up. return statement; } private void patchLimit(PreparedParameter[] params) throws IllegalPatchException { LimitExpression expn = suffixExpn.getLimitExpn(); if (expn == null) { // no limit expn, nothing to do return; } PatchedLimitExpression patchedExp = expn.patch(params); if (statement instanceof Query<?>) { Query<?> query = (Query<?>)statement; query.limit(patchedExp.getLimitValue()); } else { String msg = "Patching of non-query types not (yet) supported! Class was:" + statement.getClass().getName(); IllegalStateException invalid = new IllegalStateException(msg); throw new IllegalPatchException(invalid); } } private void patchSort(PreparedParameter[] params) throws IllegalPatchException { SortExpression expn = suffixExpn.getSortExpn(); if (expn == null) { // no sort expn, nothing to do return; } PatchedSortExpression patchedExp = expn.patch(params); if (statement instanceof Query<?>) { Query<?> query = (Query<?>)statement; PatchedSortMember[] members = patchedExp.getSortMembers(); for (int i = 0; i < members.length; i++) { query.sort(members[i].getSortKey(), members[i].getDirection()); } } else { String msg = "Patching of non-query types not (yet) supported! Class was:" + statement.getClass().getName(); IllegalStateException invalid = new IllegalStateException(msg); throw new IllegalPatchException(invalid); } } private void patchWhere(PreparedParameter[] params) throws IllegalPatchException { WhereExpression expn = suffixExpn.getWhereExpn(); if (expn == null) { // no where, nothing to do return; } // walk the tree, create actual expressions and patch values along // the way. PatchedWhereExpression patchedExp = expn.patch(params); Expression whereClause = patchedExp.getExpression(); if (statement instanceof Query<?>) { Query<?> query = (Query<?>)statement; query.where(whereClause); } else { String msg = "Patching of non-query types not (yet) supported! Class was:" + statement.getClass().getName(); IllegalStateException invalid = new IllegalStateException(msg); throw new IllegalPatchException(invalid); } } public void setNumFreeParams(int num) { this.numParams = num; } public void setSuffixExpression(SuffixExpression tree) { this.suffixExpn = tree; } public SuffixExpression getSuffixExpression() { return suffixExpn; } }