diff --git a/src/_upm.i b/src/_upm.i
index 7686e018..02a7b032 100644
--- a/src/_upm.i
+++ b/src/_upm.i
@@ -1,77 +1,110 @@
-/* Macro for adding JAVA run
-    usage: JAVA_ADD_INSTALLISR(javaupm_a110x)
+/*
+ * This file provides additional non-wrapper code functionality for use
+ * throughout the UPM repository.  This file is intended to be %imported
+ * from the top-level upm.i (not directly by UPM libraries).
+ *
+ * No wrapper code will be generated from importing this .i file.
+ */
+
+
+/* Macro for adding JAVA installISR w/runnable.
+    UPM_Classname - UPM class name w/namespace.
+
+    example usage: JAVA_ADD_INSTALLISR(upm::A110x)
 */
 %define JAVA_ADD_INSTALLISR(UPM_Classname)
 %extend UPM_Classname {
-    void installISR(jobject runnable)
-    {
-        $self->installISR(mraa_java_isr_callback, runnable);
-    }
+void installISR(jobject runnable)
+{
+    $self->installISR(mraa_java_isr_callback, runnable);
+}
 }
 %enddef
 
-/* Define GETTER in the appropiate .i file with the getter function name
+/* Macro for adding JAVA installISR w/runnable for a GPIO
+    UPM_Classname - UPM class name w/namespace.
+
+    example usage: JAVA_ADD_INSTALLISR_GPIO(upm::A110x)
+
+    Requires: Define GETTER in the appropiate .i file with the getter
+    function name.
 */
 %define JAVA_ADD_INSTALLISR_GPIO(UPM_Classname)
 %extend UPM_Classname {
-    void installISR(int gpio, mraa::Edge level, jobject runnable)
-    {
-      // delete any existing ISR and GPIO context
-      $self->uninstallISR();
+void installISR(int gpio, mraa::Edge level, jobject runnable)
+{
+  /* delete any existing ISR and GPIO context */
+  $self->uninstallISR();
 
-      // create gpio context
-      mraa::Gpio* swg_gpioIntr = $self->GETTER;
+  /* create gpio context */
+  mraa::Gpio* swg_gpioIntr = $self->GETTER;
 
-      swg_gpioIntr->dir(mraa::DIR_IN);
-      swg_gpioIntr->isr(level, runnable);
-
-    }
+  swg_gpioIntr->dir(mraa::DIR_IN);
+  swg_gpioIntr->isr(level, runnable);
+}
 }
 %enddef
 
-/* Define INTERRUPT in the appropiate .i file with the interrupt type
+/* Macro for adding JAVA installISR for GPIO interrupt w/runnable.
+    UPM_Classname - UPM class name w/namespace.
+
+    example usage: JAVA_ADD_INSTALLISR_INTERRUPT(upm::A110x)
+
+    Requires: Define INTERRUPT in the appropiate .i file with the
+    interrupt type.
 */
 %define JAVA_ADD_INSTALLISR_INTERRUPT(UPM_Classname)
 %extend UPM_Classname {
-    void installISR(INTERRUPT intr, int gpio,
-                    mraa::Edge level, jobject runnable)
-    {
-        $self->installISR(intr, gpio, level, mraa_java_isr_callback, runnable);
-    }
+void installISR(INTERRUPT intr, int gpio,
+                mraa::Edge level, jobject runnable)
+{
+    $self->installISR(intr, gpio, level, mraa_java_isr_callback, runnable);
+}
 }
 %enddef
 
+/* Macro for adding JAVA installISR for mraa::Edge w/runnable.
+    UPM_Classname - UPM class name w/namespace.
+
+    example usage: JAVA_ADD_INSTALLISR_EDGE(upm::A110x)
+*/
 %define JAVA_ADD_INSTALLISR_EDGE(UPM_Classname)
 %extend UPM_Classname {
-    void installISR(mraa::Edge level, jobject runnable)
-    {
-      $self->installISR(level, mraa_java_isr_callback, runnable);
-    }
+void installISR(mraa::Edge level, jobject runnable)
+{
+  $self->installISR(level, mraa_java_isr_callback, runnable);
+}
 }
 %enddef
 
+/* Macro for adding JAVA installISR for pin w/runnable.
+    UPM_Classname - UPM class name w/namespace.
+
+    example usage: JAVA_ADD_INSTALLISR_PIN(upm::A110x)
+*/
 %define JAVA_ADD_INSTALLISR_PIN(UPM_Classname)
 %extend UPM_Classname {
-    void installISR(int pin, jobject runnable)
-    {
-        $self->installISR(pin, mraa_java_isr_callback, runnable);
-    }
-
+void installISR(int pin, jobject runnable)
+{
+    $self->installISR(pin, mraa_java_isr_callback, runnable);
+}
 }
 %enddef
 
-/* Macro for adding JNI loadLibrary dependency
-    usage: JAVA_JNI_LOADLIBRARY(javaupm_rhusb)
+/* Macro for adding JNI loadLibrary dependency.
+    MyModuleName: Target UPM JAVA package.
+
+    example usage: JAVA_JNI_LOADLIBRARY(javaupm_rhusb)
 */
 %define JAVA_JNI_LOADLIBRARY(MyModuleName)
 %pragma(java) jniclasscode=%{
 static {
-    try {
-        System.loadLibrary("MyModuleName");
-    } catch (UnsatisfiedLinkError e) {
-        System.err.println("Native code library (MyModuleName) failed to load. \n" + e);
-        System.exit(1);
-    }
+try {
+    System.loadLibrary("MyModuleName");
+} catch (UnsatisfiedLinkError e) {
+    System.err.println("Native code library (MyModuleName) failed to load. \n" + e);
+    System.exit(1);
+}
 }
 %}
 %enddef