Fix return type of Native#loadLibrary to match unconstrained generic …

CHANGES.md

@@ -33,6 +33,7 @@ Bug Fixes
 * [#549](https://github.com/java-native-access/jna/pull/549): Fixed bug in types derived from XID - [@twall](https://github.com/twall).
 * [#536](https://github.com/java-native-access/jna/pull/536): Fixed bug in determining the Library and options associated with types defined outside of a Library - [@twall](https://github.com/twall).
 * [#531](https://github.com/java-native-access/jna/pull/531): Ensure direct-mapped callbacks use the right calling convention - [@twall](https://github.com/twall).
+* [#566](https://github.com/java-native-access/jna/pull/566): Fix return type of Native#loadLibrary to match unconstrained generic [@lgoldstein](https://github.com/lgoldstein)
 
 Release 4.2.1
 =============

contrib/platform/src/com/sun/jna/platform/mac/MacFileUtils.java

@@ -32,7 +32,7 @@ public class MacFileUtils extends FileUtils {
 
     public interface FileManager extends Library {
 
-        public FileManager INSTANCE = (FileManager)Native.loadLibrary("CoreServices", FileManager.class);
+        FileManager INSTANCE = Native.loadLibrary("CoreServices", FileManager.class);
 
         int kFSFileOperationDefaultOptions = 0;
         int kFSFileOperationsOverwrite = 0x01;

contrib/platform/src/com/sun/jna/platform/unix/X11.java

@@ -278,7 +278,7 @@ class XImage extends PointerType { }
 
     /** Definition (incomplete) of the Xext library. */
     interface Xext extends Library {
-        Xext INSTANCE = (Xext)Native.loadLibrary("Xext", Xext.class);
+        Xext INSTANCE = Native.loadLibrary("Xext", Xext.class);
         // Shape Kinds
         int ShapeBounding = 0;
         int ShapeClip = 1;
@@ -296,7 +296,7 @@ void XShapeCombineMask(Display display, Window window, int dest_kind,
 
     /** Definition (incomplete) of the Xrender library. */
     interface Xrender extends Library {
-        Xrender INSTANCE = (Xrender)Native.loadLibrary("Xrender", Xrender.class);
+        Xrender INSTANCE = Native.loadLibrary("Xrender", Xrender.class);
         class XRenderDirectFormat extends Structure {
             public short red, redMask;
             public short green, greenMask;
@@ -338,7 +338,7 @@ protected List getFieldOrder() {
     /** Definition of the Xevie library. */
     interface Xevie extends Library {
         /** Instance of Xevie. Note: This extension has been removed from xorg/xserver on Oct 22, 2008 because it is broken and maintainerless. */
-        Xevie INSTANCE = (Xevie)Native.loadLibrary("Xevie", Xevie.class);
+        Xevie INSTANCE = Native.loadLibrary("Xevie", Xevie.class);
         int XEVIE_UNMODIFIED = 0;
         int XEVIE_MODIFIED   = 1;
         // Bool XevieQueryVersion (Display* display, int* major_version, int* minor_version);
@@ -355,7 +355,7 @@ interface Xevie extends Library {
 
     /** Definition of the XTest library. */
     interface XTest extends Library {
-        XTest INSTANCE = (XTest)Native.loadLibrary("Xtst", XTest.class);///usr/lib/libxcb-xtest.so.0
+        XTest INSTANCE = Native.loadLibrary("Xtst", XTest.class);///usr/lib/libxcb-xtest.so.0
         boolean XTestQueryExtension(Display display, IntByReference event_basep, IntByReference error_basep, IntByReference majorp, IntByReference minorp);
         boolean XTestCompareCursorWithWindow(Display display, Window window, Cursor cursor);
         boolean XTestCompareCurrentCursorWithWindow(Display display, Window window);
@@ -393,7 +393,7 @@ protected List getFieldOrder() {
         }
     }
 
-    X11 INSTANCE = (X11)Native.loadLibrary("X11", X11.class);
+    X11 INSTANCE = Native.loadLibrary("X11", X11.class);
 
     /*
       typedef struct {

contrib/platform/src/com/sun/jna/platform/win32/Msi.java

@@ -20,78 +20,77 @@
  */
 public interface Msi extends StdCallLibrary {
 
-    Msi INSTANCE = (Msi)
-        Native.loadLibrary("msi", Msi.class, W32APIOptions.DEFAULT_OPTIONS);
+    Msi INSTANCE = Native.loadLibrary("msi", Msi.class, W32APIOptions.DEFAULT_OPTIONS);
 
     /**
      * The component being requested is disabled on the computer.
      */
-    static int INSTALLSTATE_NOTUSED = -7;
+    int INSTALLSTATE_NOTUSED = -7;
 
     /**
      * The configuration data is corrupt.
      */
-    static int INSTALLSTATE_BADCONFIG = -6;
+    int INSTALLSTATE_BADCONFIG = -6;
 
     /**
      * The installation is suspended or in progress.
      */
-    static int INSTALLSTATE_INCOMPLETE = -5;
+    int INSTALLSTATE_INCOMPLETE = -5;
 
     /**
      * The feature must run from the source, and the source is unavailable.
      */
-    static int INSTALLSTATE_SOURCEABSENT = -4;
+    int INSTALLSTATE_SOURCEABSENT = -4;
 
     /**
      * The return buffer is full.
      */
-    static int INSTALLSTATE_MOREDATA = -3;
+    int INSTALLSTATE_MOREDATA = -3;
 
     /**
      * An invalid parameter was passed to the function.
      */
-    static int INSTALLSTATE_INVALIDARG = -2;
+    int INSTALLSTATE_INVALIDARG = -2;
 
     /**
      * An unrecognized product or feature was specified.
      */
-    static int INSTALLSTATE_UNKNOWN = -1;
+    int INSTALLSTATE_UNKNOWN = -1;
 
     /**
      * The feature is broken.
      */
-    static int INSTALLSTATE_BROKEN =  0;
+    int INSTALLSTATE_BROKEN =  0;
 
     /**
      * The advertised feature.
      */
-    static int INSTALLSTATE_ADVERTISED =  1;
+    int INSTALLSTATE_ADVERTISED =  1;
 
     /**
      * The component is being removed.
      */
-    static int INSTALLSTATE_REMOVED =  1;
+    int INSTALLSTATE_REMOVED =  1;
 
     /**
      * The feature was uninstalled.
      */
-    static int INSTALLSTATE_ABSENT =  2;
+    int INSTALLSTATE_ABSENT =  2;
 
     /**
      * The feature was installed on the local drive.
      */
-    static int INSTALLSTATE_LOCAL =  3;
+    int INSTALLSTATE_LOCAL =  3;
 
     /**
      * The feature must run from the source, CD-ROM, or network.
      */
-    static int INSTALLSTATE_SOURCE =  4;
+    int INSTALLSTATE_SOURCE =  4;
 
     /**
      * The feature is installed in the default location: local or source.
      */
-    static int INSTALLSTATE_DEFAULT =  5;
+    int INSTALLSTATE_DEFAULT =  5;
 
     /**
      * The MsiGetComponentPath function returns the full path to an installed component. If the key path for the

contrib/platform/src/com/sun/jna/platform/win32/SetupApi.java

@@ -29,8 +29,7 @@
  */
 public interface SetupApi extends StdCallLibrary {
 
-    SetupApi INSTANCE = (SetupApi)
-        Native.loadLibrary("setupapi", SetupApi.class, W32APIOptions.DEFAULT_OPTIONS);
+    SetupApi INSTANCE = Native.loadLibrary("setupapi", SetupApi.class, W32APIOptions.DEFAULT_OPTIONS);
 
     /**
      * The GUID_DEVINTERFACE_DISK device interface class is defined for hard disk storage devices.
@@ -82,7 +81,6 @@ public interface SetupApi extends StdCallLibrary {
      * Removable.
      */
     int CM_DEVCAP_REMOVABLE = 0x00000004;
-
 
 	/** make change in all hardware profiles */
 	int DICS_FLAG_GLOBAL = 0x00000001;
@@ -94,23 +92,22 @@ public interface SetupApi extends StdCallLibrary {
 	/**
 	 * Open/Create/Delete device key.
 	 * 
-         * @see #SetupDiOpenDevRegKey
+     * @see #SetupDiOpenDevRegKey
 	 */
-
 	int DIREG_DEV = 0x00000001;
+
 	/**
 	 * Open/Create/Delete driver key
 	 * 
-         * @see #SetupDiOpenDevRegKey
+     * @see #SetupDiOpenDevRegKey
 	 */
-
 	int DIREG_DRV = 0x00000002;
+
 	/**
 	 * Delete both driver and Device key
 	 * 
-         * @see #SetupDiOpenDevRegKey
+     * @see #SetupDiOpenDevRegKey
 	 */
-
 	int DIREG_BOTH = 0x00000004;
 
 	/**
@@ -124,7 +121,6 @@ public interface SetupApi extends StdCallLibrary {
 	 */
 	int SPDRP_DEVICEDESC = 0x00000000;
 
-
     /**
      * The SetupDiGetClassDevs function returns a handle to a device information set that contains requested device
      * information elements for a local computer.

contrib/platform/src/com/sun/jna/platform/win32/Version.java

@@ -22,8 +22,7 @@
  */
 public interface Version extends StdCallLibrary {
 
-    Version INSTANCE = (Version)
-        Native.loadLibrary("version", Version.class, W32APIOptions.DEFAULT_OPTIONS);
+    Version INSTANCE = Native.loadLibrary("version", Version.class, W32APIOptions.DEFAULT_OPTIONS);
 
     /**
      * Determines whether the operating system can retrieve version information for a specified file. If version

contrib/platform/test/com/sun/jna/platform/win32/VersionUtilTest.java

@@ -23,21 +23,20 @@ public static void main(String[] args) {
     }
 
     public void testGetFileVersionNumbers() {
-        String testFileName = "regedit.exe";
-        File file = new File(System.getenv("SystemRoot"), testFileName);
-        assertTrue("Test file with version info in it should exist.", file.exists());
+        File file = new File(System.getenv("SystemRoot"), "regedit.exe");
+        assertTrue("Test file with version info in it should exist: " + file, file.exists());
 
         VS_FIXEDFILEINFO version = VersionUtil.getFileVersionInfo(file.getAbsolutePath());
         assertNotNull("Version info should have been returned.", version);
 
-        assertTrue("The major file version number should be greater than 0 when pulling version from \"" + testFileName + "\"", version.getFileVersionMajor() > 0);
-        assertTrue("The minor file version number should be greater than or equal to 0 when pulling version from \"" + testFileName + "\"", version.getFileVersionMinor() >= 0);
-        assertTrue("The revision file version number should be greater than or equal to 0 when pulling version from \"" + testFileName + "\"", version.getFileVersionRevision() >= 0);
-        assertTrue("The build file version number should be greater than or equal to 0  when pulling version from \"" + testFileName + "\"", version.getFileVersionBuild() > 0);
-        
-        assertTrue("The major product version number should be greater than 0 when pulling version from \"" + testFileName + "\"", version.getProductVersionMajor() > 0);
-        assertTrue("The minor product version number should be greater than or equal to 0 when pulling version from \"" + testFileName + "\"", version.getProductVersionMinor() >= 0);
-        assertTrue("The revision product version number should be greater than or equal to 0 when pulling version from \"" + testFileName + "\"", version.getProductVersionRevision() >= 0);
-        assertTrue("The build product version number should be greater than or equal to 0  when pulling version from \"" + testFileName + "\"", version.getProductVersionBuild() > 0);
+        assertTrue("The major file version number should be greater than 0 when pulling version from \"" + file + "\"", version.getFileVersionMajor() > 0);
+        assertTrue("The minor file version number should be greater than or equal to 0 when pulling version from \"" + file + "\"", version.getFileVersionMinor() >= 0);
+        assertTrue("The revision file version number should be greater than or equal to 0 when pulling version from \"" + file + "\"", version.getFileVersionRevision() >= 0);
+        assertTrue("The build file version number should be greater than or equal to 0  when pulling version from \"" + file + "\"", version.getFileVersionBuild() > 0);
+
+        assertTrue("The major product version number should be greater than 0 when pulling version from \"" + file + "\"", version.getProductVersionMajor() > 0);
+        assertTrue("The minor product version number should be greater than or equal to 0 when pulling version from \"" + file + "\"", version.getProductVersionMinor() >= 0);
+        assertTrue("The revision product version number should be greater than or equal to 0 when pulling version from \"" + file + "\"", version.getProductVersionRevision() >= 0);
+        assertTrue("The build product version number should be greater than or equal to 0  when pulling version from \"" + file + "\"", version.getProductVersionBuild() > 0);
     }
 }

src/com/sun/jna/Native.java

@@ -446,7 +446,7 @@ public static List<String> toStringList(char[] buf, int offset, int len) {
      * @throws UnsatisfiedLinkError if the library cannot be found or
      * dependent libraries are missing.
      */
-    public static <T extends Library> T loadLibrary(Class<T> interfaceClass) {
+    public static <T> T loadLibrary(Class<T> interfaceClass) {
         return loadLibrary(null, interfaceClass);
     }
 
@@ -465,7 +465,7 @@ public static <T extends Library> T loadLibrary(Class<T> interfaceClass) {
      * dependent libraries are missing.
      * @see #loadLibrary(String, Class, Map)
      */
-    public static <T extends Library> T loadLibrary(Class<T> interfaceClass, Map options) {
+    public static <T> T loadLibrary(Class<T> interfaceClass, Map options) {
         return loadLibrary(null, interfaceClass, options);
     }
 
@@ -483,7 +483,7 @@ public static <T extends Library> T loadLibrary(Class<T> interfaceClass, Map opt
      * dependent libraries are missing.
      * @see #loadLibrary(String, Class, Map)
      */
-    public static <T extends Library> T loadLibrary(String name, Class<T> interfaceClass) {
+    public static <T> T loadLibrary(String name, Class<T> interfaceClass) {
         return loadLibrary(name, interfaceClass, Collections.emptyMap());
     }
 
@@ -503,7 +503,12 @@ public static <T extends Library> T loadLibrary(String name, Class<T> interfaceC
      * @throws UnsatisfiedLinkError if the library cannot be found or
      * dependent libraries are missing.
      */
-    public static <T extends Library> T loadLibrary(String name, Class<T> interfaceClass, Map options) {
+    public static <T> T loadLibrary(String name, Class<T> interfaceClass, Map options) {
+        if (!Library.class.isAssignableFrom(interfaceClass)) {
+            throw new IllegalArgumentException("Interface (" + interfaceClass.getSimpleName() + ")"
+                    + " of library=" + name + " does not extend " + Library.class.getSimpleName());
+        }
+
         Library.Handler handler = new Library.Handler(name, interfaceClass, options);
         ClassLoader loader = interfaceClass.getClassLoader();
         Object proxy = Proxy.newProxyInstance(loader, new Class[] {interfaceClass}, handler);
@@ -1396,7 +1401,7 @@ public static boolean registered(Class<?> cls) {
     /** Unregister the native methods for the given class. */
     private static native void unregister(Class<?> cls, long[] handles);
 
-    private static String getSignature(Class<?> cls) {
+    static String getSignature(Class<?> cls) {
         if (cls.isArray()) {
             return "[" + getSignature(cls.getComponentType());
         }

test/com/sun/jna/AnnotatedLibraryTest.java

@@ -68,8 +68,7 @@ public Class nativeType() {
         });
 
         options.put(Library.OPTION_TYPE_MAPPER, mapper);
-        AnnotationTestLibrary lib = (AnnotationTestLibrary) 
-            Native.loadLibrary("testlib", AnnotationTestLibrary.class, options);
+        AnnotationTestLibrary lib = Native.loadLibrary("testlib", AnnotationTestLibrary.class, options);
         assertEquals("Failed to convert integer return to boolean TRUE", true,
                      lib.returnInt32Argument(true));
         assertTrue("Failed to get annotation from ParameterContext", hasAnnotation[0]);