You can use Expressions windows: while debugging, menu window -> Show View -> Expressions, then it has place to type variables of which you need to see contents
This video does an excellent job of showing you how to set breakpoints and watch variables in the Eclipse Debugger. http://youtu.be/9gAjIQc4bPU
You can do so by these ways.
Add watchpoint and while debugging you can see variable in debugger window perspective under variable tab.
OR
Add System.out.println("variable = " + variable); and see in console.
You can add a watchpoint for each variable you're interested in.
A watchpoint is a special breakpoint that stops the execution of an application whenever the value of a given expression changes, without specifying where it might occur. Unlike breakpoints (which are line-specific), watchpoints are associated with files. They take effect whenever a specified condition is true, regardless of when or where it occurred. You can set a watchpoint on a global variable by highlighting the variable in the editor, or by selecting it in the Outline view.
Source: Stackoverflow.com