Fail fast when no matching resource is found

[evpaassen]

Consider the following code:

import com.opengamma.elsql.ElSql;
import com.opengamma.elsql.ElSqlConfig;

public class Test {

    public static void main(String[] args) {
        ElSql bundle = ElSql.of(ElSqlConfig.DEFAULT, Test.class);
        bundle.getSql("test");
    }
}

There is no matching .elsql resource and an exception will occur when when retrieving the 'test' fragment:

Exception in thread "main" java.lang.IllegalArgumentException: Unknown fragment name: test
    at com.opengamma.elsql.SqlFragments.getFragment(SqlFragments.java:172)
    at com.opengamma.elsql.SqlFragments.getSql(SqlFragments.java:153)
    at com.opengamma.elsql.ElSql.getSql(ElSql.java:141)
    at Test.main(Test.java:8)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

Process finished with exit code 1

My suggestion is to fail fast when there is no matching resource at all and provide a clear error message in that case. This will make debugging a little bit easier when you're just getting to know this library.