Data Source Java Library - About This Guide

This Guide describes how to use the Google Visualization Data Source Library to implement a data source.

This guide provides a Getting Started tutorial section after the concepts in the Introduction. This approach lets you create a simple data source and test it using a visualization. The other tutorial sections are Using an External Data Store and Defining Capabilities and the Flow of Events, which cover more complex implementations. Depending on your requirements, you might not need to complete all three tutorials, though it is recommended that you at least complete the Getting Started section. The other sections of the guide help you to build on your knowledge.

Contents

Audience

You need to be familiar with Java and Java servlet technology to use the library.

You also need to understand how to use charts, and though not essential, it is helpful to be familiar with the Google Visualization API wire protocol, and the query language.

Guide Overview

This guide contains the following sections:

  • Introduction

    Introduces the library, providing an overview of how a data source works.

  • Installation

    Describes the library's prerequisites and dependencies, and how to download and build the source code.

  • Getting Started

    Introduces SimpleExampleServlet. SimpleExampleServlet is the simplest example implementation that is provided with the library. This section also provides step-by-step instructions on how to run and test SimpleExampleServlet.

  • Using an External Data Store

    Introduces CsvDataSourceServlet. CsvDataSourceServlet is an example implementation that uses a CSV file as an external data store. This section also provides step-by-step instructions on how to run and test CsvDataSourceServlet.

  • Defining Capabilities and the Flow of Events

    Introduces AdvancedExampleServlet2. AdvancedExampleServlet2 is an example implementation that defines capabilities and flow of events. This section also provides step-by-step instructions on how to run and test AdvancedExampleServlet2.

  • Handling Security, Errors, Warnings, and Logging

    Describes how to make your data source secure, and how to handle errors, warnings, and logging.

  • Implementation Tips

    Provides information that will help you write more complex implementations of the library.

  • Library Packages and Key Classes

    Provides a high level introduction to the library's packages and key classes.

Examples Quick Reference

The library is provided with six example implementations. Three of these are described in this Guide, the others are not. The following table will help you find an example of the type of behavior you want to implement.

Example Servlet extended Capabilities Flow of events Source of data
SimpleExampleServlet
Described in Getting Started
DataSourceServlet
NONE Default Within class
CsvDataSourceServlet
Described in Using an External Data Store
DataSourceServlet NONE Default CSV file
AdvancedExampleServlet2
Described in Defining Capabilities and the Flow of Events
HttpServlet SELECT Custom Within class
SimpleExampleServlet2
Not described in this Guide
HttpServlet
NONE Custom Within class
AdvancedExampleServlet
Not described in this Guide
DataSourceServlet SELECT Default Within class
SqlDataSourceServlet
Not described in this Guide
DataSourceServlet SQL Default SQL database

More Information

For information on the Data Source Library project, see the home page.