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Note: the instructions at this link are good but things have changed a bit for Forge 1.7: http://www.minecraftforge.net/wiki/Crafting_and_Smelting

Different types of mods require different types of code. One of the easiest type of mod to add is a crafting recipe. We will write one to turn some dirt into diamonds.

The code for this goes into the init function:

What this does:

• Create a new ItemStack called dirtStack with a single dirt block
• Create a new ItemStack called diamonds10 with 10 diamond blocks
• Add a new recipe to the game that will produce this stack of 10 diamonds, when you lay out the dirt in the shape specified: x in the shape is where the dirt blocks have to go.

We can also have shapeless recipes (where it doesn’t matter where you put blocks), which are even simpler to write:

GameRegistry.addShapelessRecipe(
new ItemStack(Items.diamond, 6), new ItemStack(Blocks.dirt));

This second one creates a stack of 6 diamonds from a single block of dirt.

Previous post: ModderDojo Java Modding 5: Creating Our First Mod – The Basic Code
This concludes this series of posts on getting started with Java Modding, from ModderDojo Athenry.

Previous post: ModderDojo Java Modding 4: Creating Our First Mod – Getting Started
Next post: ModderDojo Java Modding 6: Creating Our First Mod – Adding A Crafting Recipe

There is an example mod that does nothing in src/main/java, in the package com.example.examplemod. We will make a new one based on this.

Start by making a new package in the same folder, where we will put our own code. Click on src/main/java, then from the menu select File – New – Package, and pick a package name:

Now create a class in it: File – New – Class and give it a name. There is no need to select the “public static void main” option; we will be replacing all the code.

From in ExampleMod.java, copy all of the code, then delete all of the code in your own class and paste in the code from ExampleMod. Now make some changes:

• On the top line, change the package statement: it has to correspond to the package you created your class in. Eclipse will flag the error with a red line and its quick fix will allow you to change the package.
• On the line public class ExampleMod, change ExampleMod to the name of your class. In Java, the file name and class name have to be identical.
• Check that the @Mod statement refers to your class, not ExampleMod. Note: statements beginning with @ in Java are called annotations.
• In the body of your class, change the values of the variables MODID and VERSION.
• If you like, change the System.out.println line to print a new message to the console window, e.g. “Craft1 mod initialised.” Lots of messages are displayed in the console window when Minecraft runs; you should see your message near the end.

Now run Minecraft and see if your mod exists. The name should be there and your hello message on the console, but it doesn’t do anything because we haven’t added code for anything useful.

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Previous post: ModderDojo Java Modding 3: Getting Started With Eclipse
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Start up Eclipse and select the workspace that Forge created, in the Eclipse folder under Forge:

Note: if the workspace is empty, make sure that you ran the command gradlew eclipse and that you selected the correct folder.

Press the green Run icon: you should see messages in the Eclipse console window and Minecraft will launch and will initially have 4 mods.

Previous post: ModderDojo Java Modding 3: Getting Started With Eclipse
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