/*
* Copyright 2012 MyBatis.org.
*
* Licensed 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.ibatis.submitted.language;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;
import org.apache.ibatis.builder.BuilderException;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.session.Configuration;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.runtime.RuntimeSingleton;
import org.apache.velocity.runtime.parser.node.SimpleNode;
/**
* Just a test case. Not a real Velocity implementation.
*/
public class VelocitySqlSource implements SqlSource {
public static final String PARAMETER_OBJECT_KEY = "_parameter";
public static final String DATABASE_ID_KEY = "_databaseId";
private final Configuration configuration;
private final Template script;
static {
Velocity.init();
}
public VelocitySqlSource(Configuration configuration, String scriptText) {
this.configuration = configuration;
try {
RuntimeServices runtimeServices = RuntimeSingleton.getRuntimeServices();
StringReader reader = new StringReader(scriptText);
SimpleNode node = runtimeServices.parse(reader, "Template name");
script = new Template();
script.setRuntimeServices(runtimeServices);
script.setData(node);
script.initDocument();
} catch (Exception ex) {
throw new BuilderException("Error parsing velocity script", ex);
}
}
public BoundSql getBoundSql(Object parameterObject) {
Map<String, Object> bindings = createBindings(parameterObject, configuration);
VelocityContext context = new VelocityContext(bindings);
StringWriter sw = new StringWriter();
script.merge(context, sw);
VelocitySqlSourceBuilder sqlSourceParser = new VelocitySqlSourceBuilder(configuration);
Class<?> parameterType = parameterObject == null ? Object.class : parameterObject.getClass();
SqlSource sqlSource = sqlSourceParser.parse(sw.toString(), parameterType);
BoundSql boundSql = sqlSource.getBoundSql(parameterObject);
for (Map.Entry<String, Object> entry : bindings.entrySet()) {
boundSql.setAdditionalParameter(entry.getKey(), entry.getValue());
}
return boundSql;
}
public static Map<String, Object> createBindings(Object parameterObject, Configuration configuration) {
Map<String, Object> bindings = new HashMap<String, Object>();
bindings.put(PARAMETER_OBJECT_KEY, parameterObject);
bindings.put(DATABASE_ID_KEY, configuration.getDatabaseId());
bindings.put("it", new IteratorParameter(bindings));
return bindings;
}
public static class IteratorParameter {
private static final String PREFIX = "__frch_";
private int count = 0;
private final Map<String, Object> bindings;
public IteratorParameter(Map<String, Object> bindings) {
this.bindings = bindings;
}
public String next(Object prop) {
StringBuilder sb = new StringBuilder();
String name = sb.append(PREFIX).append("_ITEM").append("_").append(count++).toString();
bindings.put(name, prop);
return name;
}
}
}