RFR: 8283608: Refactor 2d, beans classes javadoc to use @throws instead of @exception

[Prasanta Sadhukhan]

Prevailing JDK coding practices use "@throws" rather than "@exception".
Need to refactor remaining 2d, beans,sound classes to use @throws

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Commit messages:
 - Fix
 - Fix

Changes: https://git.openjdk.java.net/jdk/pull/7937/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7937&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283608
  Stats: 56 lines in 22 files changed: 0 ins; 1 del; 55 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7937.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7937/head:pull/7937

PR: https://git.openjdk.java.net/jdk/pull/7937