/**
*
* 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.tuscany.samples.sdo.intermediate;
import java.util.List;
import org.apache.tuscany.samples.sdo.SampleBase;
import org.apache.tuscany.samples.sdo.advanced.PrintDataGraph;
import org.apache.tuscany.samples.sdo.internal.SampleInfrastructure;
import commonj.sdo.DataObject;
import commonj.sdo.helper.HelperContext;
/**
* Demonstrates accessing the properties of a DataObject using integer property indices.
* <p>
* <h3>Running this Sample</h3> See <A HREF="../../../../../../index.html"
* target="_top">the main overview</A> for instructions on how to run this
* sample.
*/
public class AccessingDataObjectsViaPropertyIndex extends SampleBase {
HelperContext scope;
PrintDataGraph printer;
public AccessingDataObjectsViaPropertyIndex(Integer userLevel) {
/*
* Classifying this sample as intermediate, not because it is complex
* but because it's a scenario not to be encouraged for use by
* people new to SDO.
*/
super(userLevel, SAMPLE_LEVEL_INTERMEDIATE);
printer = new PrintDataGraph(SAMPLE_LEVEL_ADVANCED);
}
/**
* Predefine the property indexes.
*/
private static final int COMPANY_DEPARTMENT = 0;
private static final int COMPANY_NAME = 1;
private static final int COMPANY_EMPLOYEE_OF_MONTH = 2;
private static final int DEPARTMENT_EMPLOYEES = 0;
private static final int EMPLOYEE_NAME = 0;
private static final int EMPLOYEE_SN = 1;
private static final int EMPLOYEE_MANAGER = 2;
/**
* Execute this method in order to run the sample.
*
* @param args
*/
public static void main(String[] args) {
AccessingDataObjectsViaPropertyIndex sample =
new AccessingDataObjectsViaPropertyIndex(COMMENTARY_FOR_NOVICE);
sample.run();
}
/*
* metadata for the sample documenting the areas of SDO that are explored
*/
public static int [] CORE_FUNCTION = {
SDOFacets.GET_SET_PROPERTIES_OF_DATAOBJECT_BY_INDEX
};
public void runSample () throws Exception {
commentary(
"This sample demonstrates the use of integer index to get and set\n" +
"Property values of a DataObject. This approach is optimized for\n" +
"performance, but is fragile to changes to the Type system. It will be\n" +
"broken if someone alters the XML schema that is used to load the type system." +
"This kind of approach is well suited to a situation where the SDO code is being\n" +
"generated.");
scope = createScopeForTypes();
loadTypesFromXMLSchemaFile(scope, SampleInfrastructure.COMPANY_XSD);
DataObject company = getDataObjectFromFile(scope, SampleInfrastructure.COMPANY_DATAOBJECT_XML);
commentary("We've loaded a data graph that looks like this ...");
printer.print(company);
System.out.println(printer.getBuf());
printer.reset();
commentary("Here's how the data graph looks rendered in XML ...");
System.out.println(
scope.getXMLHelper().save(company, SampleInfrastructure.COMPANY_NAMESPACE, "company"));
commentary(
"This sample class has primitive int static constants defined for the Properties\n" +
"of the Types that the program is designed to work with, e.g.\n\n" +
"private static final int COMPANY_NAME = 2;\n\n" +
"The value of the integers is defined by the sequence the Properties\n" +
"appear in the List returned by dataObject.getType().getDeclaredProperties()\n" +
"For a type derived from an XML schema this will be the sequence they appeared in the\n" +
"schema document.\n" +
"We can use these integer values to get and set Properties on the company DataObject\n\n" +
"company.setString(COMPANY_NAME, \"MegaCorp\");\n" +
"List departments = company.getList(COMPANY_DEPARTMENT);\n" +
"List employees = department.getList(DEPARTMENT_EMPLOYEES);\n");
company.setString(COMPANY_NAME, "MegaCorp");
commentary("The sample continues, altering the data graph by using the getter\n" +
"and setter methods that take int arguments");
List departments = company.getList(COMPANY_DEPARTMENT);
DataObject department = (DataObject) departments.get(0);
List employees = department.getList(DEPARTMENT_EMPLOYEES);
DataObject employeeFromList = (DataObject) employees.get(2);
employeeFromList.detach();
DataObject newEmployee = department.createDataObject(DEPARTMENT_EMPLOYEES);
newEmployee.set(EMPLOYEE_NAME, "Al Smith");
newEmployee.set(EMPLOYEE_SN, "E0005");
newEmployee.setBoolean(EMPLOYEE_MANAGER, true);
company.set(COMPANY_EMPLOYEE_OF_MONTH, newEmployee.get(EMPLOYEE_SN));
commentary("After some more manipulation (take a look at the sample code to see the detail)\n" +
"we can examine the state of the modified graph");
printer.print(company);
System.out.println(printer.getBuf());
printer.reset();
commentary("Or rendered in XML it now looks like this ...");
System.out.println(scope.getXMLHelper().save(company, SampleInfrastructure.COMPANY_NAMESPACE, "company"));
}
}