ScriptCraft

ScriptCraft

Bukkit Plugins
14.6k Downloads

How can I type cast java object

maple3142 opened this issue · 2 comments

commented

as title

events.entityDamage(function(e){
	var en=e.getEntity();
	console.log(en);
	var LivingEntity=org.bukkit.entity.LivingEntity;
	if(en instanceof LivingEntity){
		en=(org.bukkit.entity.LivingEntity)en;//error
		if(e.getDamage()>en.getHealth()){
			e.setDamage(0);
		}
	}
});
commented

I haven't tried this online but try this version of your code:

events.entityDamage(function(e){
	var en=e.getEntity();
	console.log(en);
	var LivingEntity=Java.type("org.bukkit.entity.LivingEntity");
	if(en instanceof LivingEntity){
		en=Java.to(en,LivingEntity);
		if(e.getDamage()>en.getHealth()){
			e.setDamage(0);
		}
	}
});

I'm curious if you could save a line and do it like this:

events.entityDamage(function(e){
	var LivingEntity=Java.type("org.bukkit.entity.LivingEntity");
	var en=Java.to(  e.getEntity() , LivingEntity  ); // could throw exception?
	console.log(en); // how does this render?
	if(en instanceof LivingEntity){  // unnecessary now that it's already cast?
		if(e.getDamage()>en.getHealth()){
			e.setDamage(0);
		}
	}
});

If the check for instanceof isn't necessary then you can eliminate three more lines:

var en=Java.to(  e.getEntity() , Java.type("org.bukkit.entity.LivingEntity")  );

Related tips:
https://docs.oracle.com/javase/8/docs/technotes/guides/scripting/nashorn/api.html
https://docs.oracle.com/javase/8/docs/technotes/guides/scripting/prog_guide/javascript.html

Please let me know how this works for ya!

For questions that aren't actually issues with the software, I recommend the Google Group, where more people can see your notes.
https://groups.google.com/forum/?fromgroups#!forum/scriptcraft---scripting-minecraft

HTH

  • 👍2
commented

You don't need to typecast - Javascript is dynamic.

events.entityDamage(function(evt){
  // does evt.entity object have a 'health' property ? if so it's a living entity
  if ('health' in evt.entity) { 
    if ( evt.damage > evt.entity.health ) {
      evt.damage = 0;
    }
  }  
});

You don't need to use .getHealth() or .getDamage() - they're Javabean properties so they can be accessed in Javascript using simply .health and .damage

  • 👍1