Examples with MapLiteral org.datanucleus.store.rdbms.sql.expression.MapLiteral used on opensource projects

Example 6 with MapLiteral

use of org.datanucleus.store.rdbms.sql.expression.MapLiteral in project datanucleus-rdbms by datanucleus.

the class MapSizeMethod method getExpression.

/* (non-Javadoc)
     * @see org.datanucleus.store.rdbms.sql.method.SQLMethod#getExpression(org.datanucleus.store.rdbms.sql.expression.SQLExpression, java.util.List)
     */
public SQLExpression getExpression(SQLStatement stmt, SQLExpression expr, List<SQLExpression> args) {
    if (args != null && args.size() > 0) {
        throw new NucleusException(Localiser.msg("060015", "size", "MapExpression"));
    }
    SQLExpressionFactory exprFactory = stmt.getSQLExpressionFactory();
    if (expr instanceof MapLiteral) {
        // Just return the map length since we have the value
        Map map = (Map) ((MapLiteral) expr).getValue();
        return exprFactory.newLiteral(stmt, exprFactory.getMappingForType(int.class, false), Integer.valueOf(map.size()));
    }
    AbstractMemberMetaData ownerMmd = expr.getJavaTypeMapping().getMemberMetaData();
    RDBMSStoreManager storeMgr = stmt.getRDBMSManager();
    ClassLoaderResolver clr = stmt.getQueryGenerator().getClassLoaderResolver();
    // TODO Allow for interface keys/values, etc
    JavaTypeMapping ownerMapping = null;
    Table mapTbl = null;
    if (ownerMmd.getMap().getMapType() == MapType.MAP_TYPE_JOIN) {
        // JoinTable
        mapTbl = storeMgr.getTable(ownerMmd);
        ownerMapping = ((JoinTable) mapTbl).getOwnerMapping();
    } else if (ownerMmd.getMap().getMapType() == MapType.MAP_TYPE_KEY_IN_VALUE) {
        // ForeignKey from value table to key
        AbstractClassMetaData valueCmd = storeMgr.getNucleusContext().getMetaDataManager().getMetaDataForClass(ownerMmd.getMap().getValueType(), clr);
        mapTbl = storeMgr.getDatastoreClass(ownerMmd.getMap().getValueType(), clr);
        if (ownerMmd.getMappedBy() != null) {
            ownerMapping = mapTbl.getMemberMapping(valueCmd.getMetaDataForMember(ownerMmd.getMappedBy()));
        } else {
            ownerMapping = ((DatastoreClass) mapTbl).getExternalMapping(ownerMmd, MappingType.EXTERNAL_FK);
        }
    } else if (ownerMmd.getMap().getMapType() == MapType.MAP_TYPE_VALUE_IN_KEY) {
        // ForeignKey from key table to value
        AbstractClassMetaData keyCmd = storeMgr.getNucleusContext().getMetaDataManager().getMetaDataForClass(ownerMmd.getMap().getKeyType(), clr);
        mapTbl = storeMgr.getDatastoreClass(ownerMmd.getMap().getKeyType(), clr);
        if (ownerMmd.getMappedBy() != null) {
            ownerMapping = mapTbl.getMemberMapping(keyCmd.getMetaDataForMember(ownerMmd.getMappedBy()));
        } else {
            ownerMapping = ((DatastoreClass) mapTbl).getExternalMapping(ownerMmd, MappingType.EXTERNAL_FK);
        }
    } else {
        throw new NucleusException("Invalid map for " + expr + " in size() call");
    }
    SelectStatement subStmt = new SelectStatement(stmt, storeMgr, mapTbl, null, null);
    subStmt.setClassLoaderResolver(clr);
    JavaTypeMapping mapping = storeMgr.getMappingManager().getMappingWithDatastoreMapping(String.class, false, false, clr);
    SQLExpression countExpr = exprFactory.newLiteral(subStmt, mapping, "COUNT(*)");
    ((StringLiteral) countExpr).generateStatementWithoutQuotes();
    subStmt.select(countExpr, null);
    SQLExpression elementOwnerExpr = exprFactory.newExpression(subStmt, subStmt.getPrimaryTable(), ownerMapping);
    SQLExpression ownerIdExpr = exprFactory.newExpression(stmt, expr.getSQLTable(), expr.getSQLTable().getTable().getIdMapping());
    subStmt.whereAnd(elementOwnerExpr.eq(ownerIdExpr), true);
    JavaTypeMapping subqMapping = exprFactory.getMappingForType(Integer.class, false);
    SQLExpression subqExpr = new NumericSubqueryExpression(stmt, subStmt);
    subqExpr.setJavaTypeMapping(subqMapping);
    return subqExpr;
}