Fixes https://github.com/emacs-lsp/lsp-java/issues/18

[yyoncho]

• Registered jdt uri handler and handled the cases when the user has opened a
  file downloaded from the jdt.

[yyoncho]

Depends on emacs-lsp/lsp-mode#328

[vibhavp]

Are you sure JDT'S applyEdit is a code action, and not a request? The whole idea behind code actions is to get TextEdits from the server to be applied to a document.

[yyoncho]

@vibhavp Yes, here it is the corresponding code in the vscode java extension: https://github.com/redhat-developer/vscode-java/blob/b47708dca469d084bc2e869dd0f85ff99a4b31b9/src/extension.ts#L178

Here it is sample response from JDT:

{"jsonrpc":"2.0","id":"9","result":[{"title":"Extract to method","command":"java.apply.workspaceEdit","arguments":[{"changes":{"file:///home/kyoncho/Documents/Sources/demo/2/src/main/java/some/test/Axx.java":[{"range":{"start":{"line":5,"character":8},"end":{"line":5,"character":8}},"newText":"extracted"},{"range":{"start":{"line":5,"character":8},"end":{"line":5,"character":8}},"newText":"();"},{"range":{"start":{"line":5,"character":8},"end":{"line":5,"character":15}},"newText":""},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"\n\t"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"private"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":" "},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"void"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":" "},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"extracted"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"() {\n\t\t"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"x \u003d 10;"},{"range":{"start":{"line":6,"character":5},"end":{"line":6,"character":5}},"newText":"\n\t}"}]}}]}]}

[yyoncho]

Just to clarify - the response cited in the previous comment was for code actions. See also: microsoft/language-server-protocol#432