You are free to move or rename the directory. You can install unzip multiple copies of Eclipse in the same machine. Eclipse comes with many flavors See "Eclipse Packages" https: Eclipse performs incremented compilation, as and when a source "line" is entered. Correct all the syntax errors; and RUN the program. Unlike errors, warnings may or may not cause problems. Try to fix these warnings as well. But you can RUN your program with warnings. This will save you many agonizing hours trying to figure out how to do somethings later.
Able to use a graphics debugger to debug program is crucial in programming. It could save you countless hours guessing on what went wrong. A breakpoint suspends program execution for you to examine the internal states e. Before starting the debugger, you need to set at least one breakpoint to suspend the execution inside the program.
Set a breakpoint at main method by double-clicking on the left-margin of the line containing main.
A blue circle appears in the left-margin indicating a breakpoint is set at that line. The program begins execution but suspends its operation at the breakpoint, i. As illustrated in the following diagram, the highlighted line also pointed to by a blue arrow indicates the statement to be executed in the next step. At each of the step, examine the value of the variables in the "Variable" panel and the outputs produced by your program in the "Console" Panel , if any.
You can also place your cursor at any variable to inspect the content of the variable. Single-stepping thru the program and watching the values of internal variables and the outputs produced is the ultimate mean in debugging programs - because it is exactly how the computer runs your program! As mentioned, a breakpoint suspends program execution and let you examine the internal states of the program. To set a breakpoint on a particular statement, double-click the left-margin of that line or select "Toggle Breakpoint" from "Run" menu.
You could set a breakpoint at the statement immediately outside the loop e. Alternatively, you can place the cursor on a particular statement, and issue "Run-To-Line" from the "Run" menu to continue execution up to the line. Always terminate your current debugging session using "Terminate" or "Resume" till the end of the program. I can's stress more that mastering the use of debugger is crucial in programming. Explore the features provided by the debuggers.
Modify the Value of a Variable: You can modify the value of a variable by entering a new value in the "Variable" panel. This is handy for temporarily modifying the behavior of a program, without changing the source code. Step-Into and Step-Return: To debug a method , you need to use "Step-Into" to step into the first statement of the method. You could use "Step-Return" to return back to the caller, anywhere within the method. Alternatively, you could set a breakpoint inside a method. Suppose that your want to write a Java program, which inputs from a text file called " xxxx.
This is a little tricky under Eclipse due to:. Create the input text file called " FileIOTest. For Servlet 2. You can debug a webapp just like standalone application. For example, you can set breakpoints, single-step through the programs, etc. Eclipse Versions The various versions are: Eclipse 1.
Eclipse 2. Eclipse 3. Step 1: Download Download Eclipse from https: Step 2: Unzip To install Eclipse, simply unzip the downloaded file into a directory of your choice e. To install Eclipse: Goto http: You will receive a DMG file e. Follow the screen instructions to install Eclipse. To confirm!
You need to first install JDK. Nonetheless, you can install any package, and then add more features when needed. To install Eclipse e.
Download Eclipse from http: You will receive a tarball e. Lock Eclipse on Launcher Simply start Eclipse. Launch Eclipse Launch Eclipse by running " eclipse. Choose an appropriate directory for your workspace , i. If the "Welcome" screen shows up, close it by clicking the "cross" button next to the "Welcome" title.
Create a new Java Project For each Java application, you need to create a project to keep all the source files, classes and relevant resources. To create a new Java project: The "New Java Project" dialog pops up. In "Project name", enter " FirstProject ". Check "Use default location".
But make sure that your JDK is 1.
In "Project Layout", check "Use project folder as root for sources and class files". Push "Next" button. Uncheck "Create module-info.
The "New Java Class" dialog pops up. In "Source folder", keep the "FirstProject". In "Package", delete the content if it is not empty. In "Name", enter " Hello ". Check " public static void main String args ". Don't change the rest. Push "Finish" button. The source file " Hello. Enter the following codes: It is because Eclipse performs the so-called incremental compilation , i. To run the program, right-click anywhere on the source file " Hello.
The output "Hello, world! Nonetheless, Eclipse allows you to keep more than one programs in a project, which is handy for writing toy programs such as your tutorial exercises. Clicking the "Run" button with a "Play" icon runs the recently-run program based on the previous configuration. Try clicking on the "down-arrow" besides the "Run" button. Correcting Syntax Errors Eclipse performs incremented compilation, as and when a source "line" is entered. Debugging Programs in Eclipse Able to use a graphics debugger to debug program is crucial in programming.
Step 0: Set an Initial Breakpoint A breakpoint suspends program execution for you to examine the internal states e. Step 3: Step 4: Breakpoint, Run-To-Line, Resume and Terminate As mentioned, a breakpoint suspends program execution and let you examine the internal states of the program. Step 5: Maximizing Window Double-Clicking: You can double-click on the "header" of any panel to maximize that particular panel, and double-click again to restore it back.
This feature is particularly useful for writing source code in full panel. Shorthand Templates sysout, for, You need to reconfigure either your language switching hot-key or Eclipse. Intelli-Sense ctrl-space: You can use ctrl-space to activate the "intelli-sense" or content assist. That is, Eclipse will offer you the choices, while you are typing. Source Formatting ctrl-shift-f: Right-click on the source. Hints for Correcting Syntax Error: If there is a syntax error on a statement, a red mark will show up on the left-margin on that statement.
You could click on the "light bulb" to display the error message, and also select from the available hints for correcting that syntax error. Refactor or Rename alt-shift-r: You can rename a variable, method, class, package or even the project easily in Eclipse.
Maximizing Window Double-Clicking: AST creation java. Uncheck "Create module-info. If there is a syntax error on a statement, a red mark will show up on the left-margin on that statement. In Connection profile, set the type and connection name.
Eclipse can rename all the occurrences of the entity. Line Numbers: You can also configure many editor options, such as the number of spaces for tab. Alternatively, you can right-click on the left-margin, and check "Show Line Numbers". Error Message Hyperlink: Click on an error message will hyperlink to the corresponding source statement.
Changing Font Type and Size: Unicode Support: This sets the default character set used for file encoding, similar to VM's command-line option -Dfile. Mouse Hover-over: Eclipse allows tool builders to independently develop tools that integrate with other people's tools so seamlessly you can't tell where one tool ends and another starts. What's New Version 4.
The download file is an installer that let's you chose what packages to install. Equinox Compendium 1: Tycho MirrorRequest. APT 3: Formatting option to keep single line methods on one line including braces consolidate warning. AST creation java.