ResultSetIterator.java
/*
* 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.commons.beanutils2.sql;
import java.sql.SQLException;
import java.util.Iterator;
import java.util.NoSuchElementException;
import org.apache.commons.beanutils2.ConversionException;
import org.apache.commons.beanutils2.DynaBean;
import org.apache.commons.beanutils2.DynaClass;
/**
* <p>
* Implements {@link Iterator} returned by the {@code iterator()} method of {@link ResultSetDynaClass}. Each object returned by this iterator will be a
* {@link DynaBean} that represents a single row from the result set being wrapped.
* </p>
*/
public class ResultSetIterator implements DynaBean, Iterator<DynaBean> {
/**
* <p>
* Flag indicating whether the result set is currently positioned at a row for which we have not yet returned an element in the iteration.
* </p>
*/
protected boolean current;
/**
* <p>
* The {@link ResultSetDynaClass} we are associated with.
* </p>
*/
protected ResultSetDynaClass dynaClass;
/**
* <p>
* Flag indicating whether the result set has indicated that there are no further rows.
* </p>
*/
protected boolean eof;
/**
* <p>
* Constructs an {@code Iterator} for the result set being wrapped by the specified {@link ResultSetDynaClass}.
* </p>
*
* @param dynaClass The {@link ResultSetDynaClass} wrapping the result set we will iterate over
*/
ResultSetIterator(final ResultSetDynaClass dynaClass) {
this.dynaClass = dynaClass;
}
/**
* <p>
* Advance the result set to the next row, if there is not a current row (and if we are not already at eof).
* </p>
*
* @throws SQLException if the result set throws an exception
*/
@SuppressWarnings("resource") // getResultSet() does not allocate.
protected void advance() throws SQLException {
if (!current && !eof) {
if (dynaClass.getResultSet().next()) {
current = true;
eof = false;
} else {
current = false;
eof = true;
}
}
}
/**
* Does the specified mapped property contain a value for the specified key value?
*
* @param name Name of the property to check
* @param key Name of the key to check
* @return {@code true} if the mapped property contains a value for the specified key, otherwise {@code false}
* @throws IllegalArgumentException if there is no property of the specified name
*/
@Override
public boolean contains(final String name, final String key) {
throw new UnsupportedOperationException("FIXME - mapped properties not currently supported");
}
/**
* Gets the value of a simple property with the specified name.
*
* @param name Name of the property whose value is to be retrieved
* @return The property's value
* @throws IllegalArgumentException if there is no property of the specified name
*/
@Override
public Object get(final String name) {
if (dynaClass.getDynaProperty(name) == null) {
throw new IllegalArgumentException(name);
}
try {
return dynaClass.getObjectFromResultSet(name);
} catch (final SQLException e) {
throw new RuntimeException("get(" + name + "): SQLException: " + e);
}
}
/**
* Gets the value of an indexed property with the specified name.
*
* @param name Name of the property whose value is to be retrieved
* @param index Index of the value to be retrieved
* @return The indexed property's value
* @throws IllegalArgumentException if there is no property of the specified name
* @throws IllegalArgumentException if the specified property exists, but is not indexed
* @throws IndexOutOfBoundsException if the specified index is outside the range of the underlying property
* @throws NullPointerException if no array or List has been initialized for this property
*/
@Override
public Object get(final String name, final int index) {
throw new UnsupportedOperationException("FIXME - indexed properties not currently supported");
}
/**
* Gets the value of a mapped property with the specified name, or {@code null} if there is no value for the specified key.
*
* @param name Name of the property whose value is to be retrieved
* @param key Key of the value to be retrieved
* @return The mapped property's value
* @throws IllegalArgumentException if there is no property of the specified name
* @throws IllegalArgumentException if the specified property exists, but is not mapped
*/
@Override
public Object get(final String name, final String key) {
throw new UnsupportedOperationException("FIXME - mapped properties not currently supported");
}
/**
* Gets the {@code DynaClass} instance that describes the set of properties available for this DynaBean.
*
* @return The associated DynaClass
*/
@Override
public DynaClass getDynaClass() {
return this.dynaClass;
}
/**
* <p>
* Gets {@code true} if the iteration has more elements.
* </p>
*
* @return {@code true} if the result set has another row, otherwise {@code false}
*/
@Override
public boolean hasNext() {
try {
advance();
return !eof;
} catch (final SQLException e) {
throw new RuntimeException("hasNext(): SQLException: " + e);
}
}
/**
* <p>
* Gets the next element in the iteration.
* </p>
*
* @return advance to the new row and return this
*/
@Override
public DynaBean next() {
try {
advance();
if (eof) {
throw new NoSuchElementException();
}
current = false;
return this;
} catch (final SQLException e) {
throw new RuntimeException("next(): SQLException: " + e);
}
}
/**
* <p>
* Remove the current element from the iteration. This method is not supported.
* </p>
*/
@Override
public void remove() {
throw new UnsupportedOperationException("remove()");
}
/**
* Remove any existing value for the specified key on the specified mapped property.
*
* @param name Name of the property for which a value is to be removed
* @param key Key of the value to be removed
* @throws IllegalArgumentException if there is no property of the specified name
*/
@Override
public void remove(final String name, final String key) {
throw new UnsupportedOperationException("FIXME - mapped operations not currently supported");
}
/**
* Sets the value of an indexed property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param index Index of the property to be set
* @param value Value to which this property is to be set
* @throws ConversionException if the specified value cannot be converted to the type required for this property
* @throws IllegalArgumentException if there is no property of the specified name
* @throws IllegalArgumentException if the specified property exists, but is not indexed
* @throws IndexOutOfBoundsException if the specified index is outside the range of the underlying property
*/
@Override
public void set(final String name, final int index, final Object value) {
throw new UnsupportedOperationException("FIXME - indexed properties not currently supported");
}
/**
* Sets the value of a simple property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param value Value to which this property is to be set
* @throws ConversionException if the specified value cannot be converted to the type required for this property
* @throws IllegalArgumentException if there is no property of the specified name
* @throws NullPointerException if an attempt is made to set a primitive property to null
*/
@SuppressWarnings("resource") // getResultSet() does not allocate.
@Override
public void set(final String name, final Object value) {
if (dynaClass.getDynaProperty(name) == null) {
throw new IllegalArgumentException(name);
}
try {
dynaClass.getResultSet().updateObject(name, value);
} catch (final SQLException e) {
throw new RuntimeException("set(" + name + "): SQLException: " + e);
}
}
/**
* Sets the value of a mapped property with the specified name.
*
* @param name Name of the property whose value is to be set
* @param key Key of the property to be set
* @param value Value to which this property is to be set
* @throws ConversionException if the specified value cannot be converted to the type required for this property
* @throws IllegalArgumentException if there is no property of the specified name
* @throws IllegalArgumentException if the specified property exists, but is not mapped
*/
@Override
public void set(final String name, final String key, final Object value) {
throw new UnsupportedOperationException("FIXME - mapped properties not currently supported");
}
}