/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.jdbc;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;
import org.teiid.client.metadata.MetadataResult;
import org.teiid.client.metadata.ResultsMetadataConstants;
import org.teiid.core.util.StringUtil;
import org.teiid.runtime.client.Messages;
/**
* This metadata provider starts with just column names and types (provided in the response)
* but must lazily load the rest of the metadata when necessary.
*/
public class DeferredMetadataProvider extends MetadataProvider {
private StatementImpl statement;
private long requestID;
private boolean loaded;
public DeferredMetadataProvider(String[] columnNames, String[] columnTypes, StatementImpl statement, long requestID) {
super(loadPartialMetadata(columnNames, columnTypes));
this.statement = statement;
this.requestID = requestID;
}
static Map<Integer, String>[] loadPartialMetadata(String[] columnNames, String[] columnTypes) {
if(columnNames == null || columnTypes == null || columnNames.length != columnTypes.length) {
Object[] params = new Object[] {
StringUtil.toString(columnNames), StringUtil.toString(columnTypes)
};
throw new IllegalArgumentException(Messages.getString(Messages.JDBC.DeferredMetadataProvider_Invalid_data, params));
}
Map<Integer, String>[] columnMetadata = new Map[columnNames.length];
for(int i=0; i<columnNames.length; i++) {
columnMetadata[i] = new HashMap<Integer, String>();
columnMetadata[i].put(ResultsMetadataConstants.ELEMENT_LABEL, columnNames[i]);
columnMetadata[i].put(ResultsMetadataConstants.DATA_TYPE, columnTypes[i]);
}
return columnMetadata;
}
private void loadFullMetadata() throws SQLException {
MetadataResult results;
try {
results = this.statement.getDQP().getMetadata(this.requestID);
} catch (Exception e) {
throw new SQLException(e);
}
this.metadata = results.getColumnMetadata();
}
@Override
public Object getValue(int columnIndex, Integer metadataPropertyKey) throws SQLException {
if(!loaded && !(metadataPropertyKey == ResultsMetadataConstants.ELEMENT_LABEL || metadataPropertyKey == ResultsMetadataConstants.DATA_TYPE)) {
loadFullMetadata();
loaded = true;
}
return super.getValue(columnIndex, metadataPropertyKey);
}
}