Modulese

Author: bowbahdoe

src/SUMMARY.md

@@ -566,6 +566,7 @@ Zombie Game
   - [Public Classes](./packages/public_classes.md)
   - [Fully Qualified Class Name](./packages/fully_qualified_class_name.md)
   - [Import](./packages/import.md)
+  - [Package Imports](./packages/package_imports.md)
   - [The Default Package](./packages/the_default_package.md)
   - [The Anonymous Main Class](./packages/the_anonymous_main_class.md)
   - [Public Methods](./packages/public_methods.md)
@@ -840,27 +841,32 @@ Make them do one. -->
 - [Modules](./modules.md)
   - [Declaration](./modules/declaration.md)
   - [Restrictions](./modules/restrictions.md)
-  - [Exports]()
-  - [Integrity]()
+  - [Exports](./modules/exports.md)
+  - [Requires](./modules/requires.md)
+  - [Module Imports](./modules/module_imports.md)
   - [java.base](./modules/java.base.md)
   - [The Unnamed Module](./modules/the_unnamed_module.md)
-  - [Module Imports](./modules/module_imports.md)
   - [Multi-Module Directory Layout](./modules/multi_module_directory_layout.md)
+  - [Purpose](./modules/purpose.md)
+  - [Challenges](./modules/challenges.md)
+<!--
 - [Lambdas](./lambdas.md)
   - [Functional Interfaces](./lambdas/functional_interfaces.md)
   - [@FunctionalInterface](./lambdas/functional_interface_annotation.md)
   - [Lambda Expressions](./lambdas/lambda_expressions.md)
   - [Method References](./lambdas/method_references.md)
-  - [Runnable]()
-  - [Function]()
-  - [Relation to Checked Exceptions]()
+  - [Runnable](./lambdas/runnable.md)
+  - [Function](./lambdas/function.md)
+  - [Checked Exceptions](./lambdas/checked_exceptions.md)
+  - [Challenges](./lambdas/challenges.md)
+
 - [Streams](./streams.md)
   - [map](./streams/map.md)
   - [filter](./streams/filter.md)
   - [Collectors](./streams/collectors.md)
   - [toList](./streams/toList.md)
   - [mapMulti](./streams/mapMulti.md)
-  - [Gatherers](./streams/gatherers.md)
+  - [Gatherers](./streams/gatherers.md) -->
 
 # Sharing Code
 

src/lambdas.md

@@ -1,2 +1,3 @@
 # Lambdas
 
+

src/lambdas/challenges.md

@@ -0,0 +1 @@
+# Challenges

src/lambdas/checked_exceptions.md

@@ -0,0 +1 @@
+# Checked Exceptions

src/lambdas/function.md

@@ -0,0 +1 @@
+# Function

src/lambdas/runnable.md

@@ -0,0 +1 @@
+# Runnable

src/modules/challenges.md

@@ -0,0 +1,24 @@
+# Challenges
+
+Remember the rules for this are
+
+- Try to use only the information given up to this point in this book.
+- Try not to give up until you've given it a solid attempt
+
+## Challenge 1.
+
+Add a `module-info.java` to one of your projects.
+
+## Challenge 2.
+
+Move some of your code to use the multi-module directory layout.
+If you need to split one of your projects into multiple modules
+to pull this off, do so.
+
+## Challenge 3.
+
+Intentionally create a split package situation. What error does Java give you?
+
+## Challenge 4.
+
+Intentionally create a cycle in the "module graph." What error does Java give you?

src/modules/exports.md

@@ -0,0 +1,41 @@
+# Exports
+
+Inside your `module-info.java` file you declare which packages are
+"exported" from that module.
+
+```java
+module reality {
+    exports earth;
+    exports sea;
+    exports sky;
+}
+```
+
+Any packages that do not have an `exports` declaration are "unexported packages."
+
+The classes in unexported packages will not be visible to other modules
+even if those classes are `public`.
+
+```java,no_run
+// Because the "backrooms" package is not exported
+// from the "reality" module, other modules cannot
+// observe classes within it.
+package backrooms;
+
+public class YellowCarpet {
+}
+```
+
+```java,no_run
+package sky;
+
+
+// But classes within other packages of
+// the "reality" module can see it just fine.
+public class Cloud {
+    private final YelloCarpet fabricOfExistence
+        = new YellowCarpet();
+
+    // ...
+}
+```

src/modules/module_imports.md

@@ -2,7 +2,7 @@
 
 A special kind of import is the "module import."
 
-Just like a `*` at the end of a regular import will
+Just like a package import (`import package_name.*`) will
 import all the classes in that package, an `import module`
 declaration will import all the classes in all the packages
 contained within that module.
@@ -24,4 +24,9 @@ class Main {
         IO.println(c);
     }
 }
-```
+```
+
+This has much the same upsides and downsides as a package import. It is
+much easier to write this and get all the classes you want, but in exchange
+it might be harder to see where a particular class comes from when you are
+reading code later.

src/modules/multi_module_directory_layout.md

@@ -1 +1,59 @@
 # Multi-Module Directory Layout
+
+If you yourself want to develop a project using multiple of your own modules
+there is a special way to layout the files to do so.
+
+First, make folders with the name of each module. If a module name
+has a `.` in it the folder should too.
+
+```text,no_run
+reality/
+backrooms/
+horrible.monsters/
+```
+
+Then in those folders under a `src` folder put the `module-info.java` files.[^src]
+
+```text,no_run
+reality/
+  src/
+    module-info.java
+backrooms/
+  src/
+    module-info.java
+horrible.monsters/
+  src/
+    module-info.java
+```
+
+From there you can put all the classes you want into each module, so long as they don't conflict
+or create split packages.
+
+```text,no_run
+reality/
+  src/
+    earth/
+      Dirt.java
+      Worm.java
+    sea/
+      Starfish.java
+    sky/
+      Cloud.java
+    module-info.java
+backrooms/
+  src/
+    backrooms/
+      YellowCarpet.java
+    module-info.java
+horrible.monsters/
+  src/
+    horrible/
+      monsters/
+        Slime.java
+        Skeleton.java
+    module-info.java
+```
+
+This can be helpful in structuring larger projects.
+
+[^src]: The `src` folder isn't technically required. You will see what a `--module-source-path` looks like in a bit. I think its a good idea anyways.