how to find repeated task in all projects based on application in jql

[Vivek Sharma]

i need jql query for repeated tickets in java application for multiple projects 

[Peter Masters]

You're going to need more detail than that.  JQL will let you filter on "Project = 'something'" or "Project in (project1, project2, project3)".  I would start by using the Filters->Advanced Issue Search view.  On the right of the search bar is a "Switch to basic" - start with that, and get your query roughly right, and then "Switch to JQL" and add any missing options you think you need.