[ML][docs][minor] Define LabeledDocument/Document classes in CV example

[petro-rudenko]

To easier copy/paste Cross-Validation example code snippet need to define LabeledDocument/Document in it, since they difined in a previous example.

[AmplabJenkins]

Can one of the admins verify this patch?

[srowen]

It seems reasonable, but adds a fair bit of code to the Java example. I'm not sure if the intent was that it be runnable, or simply illustrate a snippet of the core API usage. @mengxr

[mengxr]

I'm okay with this change, which makes the example self-contained and hence users can try it out easily.

[mengxr]

add to whitelist

[mengxr]

ok to test

[mengxr]

Long -> long

[SparkQA]

Test build #29051 has started for PR 5135 at commit 1d35383.

• This patch merges cleanly.

[SparkQA]

Test build #29051 has finished for PR 5135 at commit 1d35383.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • case class LabeledDocument(id: Long, text: String, label: Double)
  • case class Document(id: Long, text: String)
  • public class Document implements Serializable
  • public class LabeledDocument extends Document implements Serializable

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/29051/
Test PASSed.

[SparkQA]

Test build #29088 has started for PR 5135 at commit 5190c75.

• This patch merges cleanly.

[SparkQA]

Test build #29088 has finished for PR 5135 at commit 5190c75.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • case class LabeledDocument(id: Long, text: String, label: Double)
  • case class Document(id: Long, text: String)
  • public class Document implements Serializable
  • public class LabeledDocument extends Document implements Serializable

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/29088/
Test PASSed.

[srowen]

OK so this is intentionally duplicated from the example above? I guess that's reasonable since the point is to be self-contained, and I don't imagine there's a lot of maintenance overhead in trying to evolve both copies together.

[petro-rudenko]

Yes it's annoying when copy/pasting a bunch of code into spark shell and it fails because these classes are not declared.