java,android,performance,code-execution
You want to start with traceview in order to get an overview of where your hotspots are (if any). The rule of optimization is that you should focus only where there is a significant bottleneck. The android developer docs have a nice introduction titled Profiling with Traceview and dmtracedump online....
java,eclipse,code-generation,auto-generate,code-execution
You can specify a program or Ant script to be run when a project needs building in the 'Builders' section of the Properties for a Project. You can also write an Eclipse plugin 'Incremental Builder' using the 'org.eclipse.core.resources.builders' extension point. More information about this in the Eclipse help....