java.io.Console support in Eclipse IDE

The reason this occurs is because eclipse runs your app as a background process and not as a top-level process with a system console.

The workaround that I use is to just use System.in/System.out instead of Console when using Eclipse. For example, instead of:

String line = System.console().readLine();

You can use:

BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
String line = bufferedReader.readLine();

I assume you want to be able to use step-through debugging from Eclipse. You can just run the classes externally by setting the built classes in the bin directories on the JRE classpath.

java -cp workspace\p1\bin;workspace\p2\bin foo.Main

You can debug using the remote debugger and taking advantage of the class files built in your project.

In this example, the Eclipse project structure looks like this:

workspace\project\
                 \.classpath
                 \.project
                 \debug.bat
                 \bin\Main.class
                 \src\Main.java

1. Start the JVM Console in Debug Mode

debug.bat is a Windows batch file that should be run externally from a cmd.exe console.

@ECHO OFF
SET A_PORT=8787
SET A_DBG=-Xdebug -Xnoagent -Xrunjdwp:transport=dt_socket,address=%A_PORT%,server=y,suspend=y
java.exe %A_DBG% -cp .\bin Main

In the arguments, the debug port has been set to 8787. The suspend=y argument tells the JVM to wait until the debugger attaches.

2. Create a Debug Launch Configuration

In Eclipse, open the Debug dialog (Run > Open Debug Dialog...) and create a new Remote Java Application configuration with the following settings:

• Project: your project name
• Connection Type: Standard (Socket Attach)
• Host: localhost
• Port: 8787

3. Debugging

So, all you have to do any time you want to debug the app is:

• set a break point
• launch the batch file in a console
• launch the debug configuration

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You can track this issue in bug 122429. You can work round this issue in your application by using an abstraction layer as described here.