/*
* 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 groovy.sql;
import groovy.lang.
GroovyObjectSupport;
import groovy.lang.
MissingPropertyException;
import groovy.lang.
ReadOnlyPropertyException;
import org.codehaus.groovy.runtime.
InvokerHelper;
import java.sql.
ResultSetMetaData;
/**
* This class defines a wrapper for accessing a specific column in <code>ResultSetMetaData</code>.
* This allows iteration over columns using idiomatic Groovy, e.g.:
* <pre>
* meta.each {col ->
* println col.columnName
* }
* </pre>
* All <code>ResultSetMetaData</code> column methods taking a column index
* are available on a column either as a no-arg getter or via a property.
* <p>
* This wrapper is created by an iterator invoked for <code>ResultSetMetaData</code>.
*
* @see org.apache.groovy.sql.extensions.SqlExtensions
*/
public class
ResultSetMetaDataWrapper extends
GroovyObjectSupport {
private static final
Object[]
EMPTY_OBJECT_ARRAY = new
Object[0];
private final
ResultSetMetaData target;
private final int
index;
public
ResultSetMetaDataWrapper(
ResultSetMetaData target, int
index) {
this.
target =
target;
this.
index =
index;
}
private
Object[]
getIndexedArgs(
Object[]
originalArgs) {
Object[]
result = new
Object[
originalArgs.length + 1];
result[0] =
index;
for (int
i = 0,
originalArgsLength =
originalArgs.length;
i <
originalArgsLength;
i++) {
result[
i + 1] =
originalArgs[
i];
}
return
result;
}
@
Override
public
Object invokeMethod(
String name,
Object args) {
Object[]
indexedArgs =
getIndexedArgs((
Object[])
args);
return
InvokerHelper.
invokeMethod(
target,
name,
indexedArgs);
}
private
String getPropertyGetterName(
String prop) {
if (
prop == null ||
prop.
length() < 1) {
throw new
MissingPropertyException(
prop,
target.
getClass());
}
return "get" +
prop.
substring(0, 1).
toUpperCase() +
prop.
substring(1);
}
@
Override
public
Object getProperty(
String property) {
return
invokeMethod(
getPropertyGetterName(
property),
EMPTY_OBJECT_ARRAY);
}
@
Override
public void
setProperty(
String property,
Object newValue) {
throw new
ReadOnlyPropertyException(
property,
target.
getClass());
}
}