Integrated Development Environments, or IDEs, can greatly facilitate the task of creating applications. Mid-level code editors, such as Crimson Editor, TextPad, or Edit-Plus, provide syntax highlighting, automatic indenting, parentheses and curly-brace matching, and may have tools to compile and execute programs.
High-end environments, such as Eclipse, NetBeans, or JDeveloper, offer many additional features, such as project management, automatic deployment for web applications, code refactoring, code assist, etc. But, these additional capabilities come with the price of additional complexity in the environment, particularly because they force you to create projects for even the simplest applications.
To use the class files in these environments, we must first have a workspace, which is a collection of projects. Workspaces have various configuration settings that will cut across all projects within all projects they contain, such as which version of Java is in use, any added libraries, etc. (a project is usually one application).
Both Eclipse and NetBeans use the workspace concept, but you can start with any empty directory - the IDE will add its own special files as you create projects.
In the Windows Explorer, navigate to your ClassFiles directory. If it does not contain a Workspace subdirectory, create it.
To use Eclipse with the class files, you can direct it to the workspace
(ClassFiles/Workspace) when it opens (if it asks), or use
if Eclipse is already running. Each chapter's
demo folder should be treated as a project, as should each Solution folder.
One limitation of these environments is that no project can contain the same Java class twice, so our progressive versions of the Payroll application solution require their own individual project. Also, due to the way Java's package structures work, each Demo folder must be a separate project, as with each subdirectory under Solutions.
To use the Exercises folder as an Eclipse project:
Select File > New > Java Project
Exercisesfor the project name
Package Explorerpane, right-click on the
srcfolder under the
Importfrom the context menu
File Systemfrom the tree in the
Browsebutton, navigate to and select
c:/ClassFiles/Exercises. (Note: this path might be different depending on where you extracted the class zip file)
Exercisescheck box is selected and click
srcfolder in the
Package Explorerand then expand the
Run As... > Java Application
Consoleat the bottom of the Eclipse workbench
As we encounter each chapter, we can create a project using the Demos directory for that chapter the same way we just created the Exercises project..
To create a Java class within a project, use
, and then
if that is available, or
. Provide a name and
In general, with the several applications that we will build upon progressively (Game and Payroll), you can continue to work with the same files, and add to them as we cover additional topics. If you want to check the solutions, you can either open those files in a separate editor, like Notepad, or create a project for that Solutions subdirectory. If you wish to save a particular stage of the application for future reference, you can just make a copy of the Exercises directory.
The examples and instructions provided use a more basic text editor (Chrimson) and an OS console for clarity. You are free to choose which tool to use. If Eclipse becomes a problem, move to a simple editor. The focus of this course is on the Java Programming Language and not a particular tool.