SWIGJAVA: Remove the last JAVA ifdefs from src

Removed all references to #ifdef SWIGJAVA and JAVACALLBACK from the
library source.  All java-specific source code has been moved to the
corresponding library's .i file for java.

    * Update library source
    * Update examples where necessary
    * The function pointer methodology has been remove from libraries
      which provided callbacks as both a class and a function pointer
      implementation.  Examples were updated to use the class version
      of callbacks.
    * Updated documentation for SWIGJAVA

Signed-off-by: Noel Eck <noel.eck@intel.com>

src/mpu9150/javaupm_mpu9150.i

@@ -3,40 +3,22 @@
 %include "typemaps.i"
 %include "arrays_java.i"
 %include "../java_buffer.i"
+%include "std_vector.i"
+
+%template(FloatVector) std::vector<float>;
 
 %apply int {mraa::Edge};
 
 %{
-    #include "mpu60x0.hpp"
-    #include "mpu9150.hpp"
+#include "mpu60x0.hpp"
+#include "mpu9150.hpp"
 %}
-
-
-%typemap(jni) float * "jfloatArray"
-%typemap(jstype) float * "float[]"
-%typemap(jtype) float * "float[]"
-
-%typemap(javaout) float * {
-    return $jnicall;
-}
-
-%typemap(out) float * {
-    $result = JCALL1(NewFloatArray, jenv, 3);
-    JCALL4(SetFloatArrayRegion, jenv, $result, 0, 3, $1);
-    delete [] $1;
-}
-
-%ignore getAccelerometer(float *, float *, float *);
-%ignore getGyroscope(float *, float *, float *);
-%ignore getMagnetometer(float *, float *, float *);
-
 %include "mpu60x0.hpp"
 %include "mpu9150.hpp"
 
-%ignore installISR(int , mraa::Edge , void *, void *);
-
 %define GETTER get_gpioIRQ()
 %enddef
+
 JAVA_ADD_INSTALLISR_GPIO(upm::MPU60X0)
 
 JAVA_JNI_LOADLIBRARY(javaupm_mpu9150)

src/mpu9150/mpu9150.cxx

@@ -109,11 +109,9 @@ void MPU9150::getMagnetometer(float *x, float *y, float *z)
     *z = mz;
 }
 
-#ifdef SWIGJAVA
-float *MPU9150::getMagnetometer()
+std::vector<float> MPU9150::getMagnetometer()
 {
-    float *v = new float[3];
+    std::vector<float> v(3);
     getMagnetometer(&v[0], &v[1], &v[2]);
     return v;
 }
-#endif

src/mpu9150/mpu9150.hpp

@@ -23,6 +23,7 @@
  */
 
 #pragma once
+#include <vector>
 
 #include "mpu60x0.hpp"
 #include "ak8975.hpp"
@@ -108,17 +109,13 @@ namespace upm {
      */
     void getMagnetometer(float *x, float *y, float *z);
 
-#ifdef SWIGJAVA
     /**
      * Return the compensated values for the x, y, and z axes.  The
      * unit of measurement is in micro-teslas (uT).
      *
-     * @return Array containing X, Y, Z magnetometer values
+     * @return std::vector containing X, Y, Z magnetometer values
      */
-    float *getMagnetometer();
-#endif
-
-
+    std::vector<float> getMagnetometer();
 
   protected:
     // magnetometer instance