Catch SQLServerException

Question

I know that a method can throw an non-runtime exception, so that a calling method can either throw or catch that exception. Right now, I am not so sure of what would happen if I write something that catch a runtime exception.
Here, I am using Eclipse 3.2 and Junit 3.8.1 to catch a particular exception called SQLServerException. The following code is shown as follows:
     public void testIncorrectInput() {
          try {
               Casefile d = Casefile.load("1");
               CaseComment.load(d, "w");
          } catch (SQLServerException e) {
               System.out.println("here");
The CaseComment.load() method does not explicilty throw SQLServerException but that is where the SQLServerException is coming from. According to the Microsoft Help document, the SQLServerException extends from java.sql.SQLException which also extends from Exception. I assume that I can catch any exception regardless of whether it is a runtime exception or not. The thing is that the Eclipse complained, "Unreachable catch block for SQLServerException. This exception is never thrown from the try
statement body."
Why is this happening? Is my assumption of catching any exception wrong?

Answer 1

I commented out the try and catch keywords and run the test. This is what I get:
com.microsoft.sqlserver.jdbc.SQLServerException: Conversion failed when converting the varchar value 'w' to data type smallint.
     at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(Unknown Source)
     at com.microsoft.sqlserver.jdbc.IOBuffer.processPackets(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerStatement.buildNextRowset(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerStatement.getNextResult(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.getPrepExecResponse(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.doExecutePreparedStatement(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement$PreparedStatementExecutionRequest.executeStatement(Unknown Source)
     at com.microsoft.sqlserver.jdbc.CancelableRequest.execute(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeRequest(Unknown Source)
     at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.executeQuery(Unknown Source)
     at gov.ocda.cms2.core.CMSObject.loadDataSet(CMSObject.java:61)
     at gov.ocda.cms2.model.casefile.CaseComment.load(CaseComment.java:35)
     at junit.CaseCommentTest.testIncorrectInput(CaseCommentTest.java:37)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
     at java.lang.reflect.Method.invoke(Unknown Source)
     at junit.framework.TestCase.runTest(TestCase.java:154)
     at junit.framework.TestCase.runBare(TestCase.java:127)
     at junit.framework.TestResult$1.protect(TestResult.java:106)
     at junit.framework.TestResult.runProtected(TestResult.java:124)
     at junit.framework.TestResult.run(TestResult.java:109)
     at junit.framework.TestCase.run(TestCase.java:118)
     at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:128)
     at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
I believe that whatever code inside the try clause did throw the exception. What does it mean?