jni.pas

Borland Delphi Runtime Library } { Java Native Interface Unit

  {$EXTERNALSYM JavaVMOption}

  PJavaVMInitArgs = ^JavaVMInitArgs;
  JavaVMInitArgs = packed record
    version: JInt;
    nOptions: JInt;
    options: PJavaVMOption;
    ignoreUnrecognized: JBoolean;
  end;
  {$EXTERNALSYM JavaVMInitArgs}

  PJavaVMAttachArgs = ^JavaVMAttachArgs;
  JavaVMAttachArgs = packed record
    version: JInt;
    name: PAnsiChar;
    group: JObject;
  end;
  {$EXTERNALSYM JavaVMAttachArgs}

  {$IFDEF MSWINDOWS}
  TIOFile = Pointer; // (rom) for Kylix compatibility
  {$ENDIF}

  // These structures will be VM-specific.
  PJDK1_1InitArgs = ^JDK1_1InitArgs;
  JDK1_1InitArgs = packed record
    version: JInt;
    properties: ^PAnsiChar;
    checkSource: JInt;
    nativeStackSize: JInt;
    javaStackSize: JInt;
    minHeapSize: JInt;
    maxHeapSize: JInt;
    verifyMode: JInt;
    classpath: PAnsiChar;

    vfprintf: function(FP: TIOFile; const Format: PAnsiChar; Args: va_list): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
    exit: procedure(Code: JInt); {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
    abort: procedure; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

    enableClassGC: JInt;
    enableVerboseGC: JInt;
    disableAsyncGC: JInt;
    verbose: JInt;
    debugging: JBoolean;
    debugPort: JInt;
  end;
  {$EXTERNALSYM JDK1_1InitArgs}

  JDK1_1AttachArgs = packed record
    __padding: Pointer;
  end;
  {$EXTERNALSYM JDK1_1AttachArgs}

  // End VM-specific.

  JNIInvokeInterface_ = packed record
    reserved0: Pointer;
    reserved1: Pointer;
    reserved2: Pointer;

    DestroyJavaVM: function(PVM: PJavaVM): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
    AttachCurrentThread: function(PVM: PJavaVM; PEnv: PPJNIEnv; Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
    DetachCurrentThread: function(PVM: PJavaVM): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

    GetEnv: function(PVM: PJavaVM; PEnv: PPointer; Version: JInt): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

    // J2SDK1_4
    AttachCurrentThreadAsDaemon: function(PVM: PJavaVM; PEnv: PPJNIEnv; Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

  end;
  {$EXTERNALSYM JNIInvokeInterface_}

  // Defined by native libraries.
  TJNI_OnLoad = function(PVM: PJavaVM; Reserved: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
  TJNI_OnUnload = procedure(PVM: PJavaVM; Reserved: Pointer); {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

{$IFDEF DYNAMIC_LINKING}
function JNI_GetDefaultJavaVMInitArgs(Args: PJDK1_1InitArgs; const JVMDLLFile: string): JInt;
{$EXTERNALSYM JNI_GetDefaultJavaVMInitArgs}
function JNI_CreateJavaVM(PJVM: PJavaVM; PEnv: PPointer; Args: Pointer; const JVMDLLFile: string): JInt;
{$EXTERNALSYM JNI_CreateJavaVM}
function JNI_GetCreatedJavaVMs(PJVM: PJavaVM; JSize1: JSize; var JSize2: JSize; const JVMDLLFile: string): JInt;
{$EXTERNALSYM JNI_GetCreatedJavaVMs}
{$ELSE}
function JNI_GetDefaultJavaVMInitArgs(Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
{$EXTERNALSYM JNI_GetDefaultJavaVMInitArgs}
function JNI_CreateJavaVM(PJVM: PJavaVM; PEnv: PPointer; Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
{$EXTERNALSYM JNI_CreateJavaVM}
function JNI_GetCreatedJavaVMs(PJVM: PJavaVM; JSize1: JSize; var JSize2: JSize): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
{$EXTERNALSYM JNI_GetCreatedJavaVMs}
{$ENDIF}

// Wrapper stuff
type
  TJValueArray = array of JValue;

  EJVMError = class(Exception);
  EJNIError = class(Exception);
  EJNIUnsupportedMethodError = class(EJNIError);

  TJNI_GetDefaultJavaVMInitArgs = function(Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
  TJNI_CreateJavaVM = function(PJVM: PJavaVM; PEnv: PPointer; Args: Pointer): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}
  TJNI_GetCreatedJavaVMs = function(PJVM: PJavaVM; JSize1: JSize; var JSize2: JSize): JInt; {$IFDEF MSWINDOWS} stdcall; {$ENDIF} {$IFDEF LINUX} cdecl; {$ENDIF}

  TJavaVM = class(TObject)
  private
    FJavaVM: PJavaVM;
    FEnv: PJNIEnv;
    FJavaVMInitArgs: JavaVMInitArgs;
    FJDK1_1InitArgs: JDK1_1InitArgs;
    FJVMDLLFile: string;

    FVersion: JInt;
    {$IFDEF MSWINDOWS}
    FDLLHandle: THandle;
    {$ENDIF}
    {$IFDEF LINUX}
    FDLLHandle: Pointer;
    {$ENDIF}
    FIsInitialized: Boolean;

    // DLL functions
    FJNI_GetDefaultJavaVMInitArgs: TJNI_GetDefaultJavaVMInitArgs;
    FJNI_CreateJavaVM:             TJNI_CreateJavaVM;
    FJNI_GetCreatedJavaVMs:        TJNI_GetCreatedJavaVMs;

    procedure SetVersion(const Value: JInt);
  public
    property JavaVM: PJavaVM read FJavaVM write FJavaVM;
    property Env: PJNIEnv read FEnv write FEnv;
    property JDK1_1InitArgs: JDK1_1InitArgs read FJDK1_1InitArgs;
    property JDK1_2InitArgs: JavaVMInitArgs read FJavaVMInitArgs;
    property Version: JInt read FVersion write SetVersion;

    // Constructors
    constructor Create; overload;
    constructor Create(JDKVersion: Integer); overload;
    constructor Create(JDKVersion: Integer; const JVMDLLFilename: string); overload;

    destructor Destroy; override;
    function LoadVM(const Options: JDK1_1InitArgs): JInt; overload;
    function LoadVM(const Options: JavaVMInitArgs): JInt; overload;
    function GetDefaultJavaVMInitArgs(Args: PJDK1_1InitArgs): JInt;
    function GetCreatedJavaVMs(PJVM: PJavaVM; JSize1: JSize; var JSize2: JSize): JInt;
  end;

  TJNIEnv = class(TObject)
  private
    FEnv: PJNIEnv;
    FMajorVersion: JInt;
    FMinorVersion: JInt;
    FVersion: JInt;
    FConvertedArgs: TJValueArray;
    function GetMajorVersion: JInt;
    function GetMinorVersion: JInt;
    procedure VersionCheck(const FuncName: string; RequiredVersion: JInt);
  public
    // Properties
    property Env: PJNIEnv read FEnv;
    property MajorVersion: JInt read FMajorVersion;
    property MinorVersion: JInt read FMinorVersion;
    property Version: JInt read FVersion;

    // Constructors
    constructor Create(AEnv: PJNIEnv);

    // Support methods
    function ArgsToJValues(const Args: array of const): PJValue;
    function JStringToString(JStr: JString): string;
    function StringToJString(const AString: PAnsiChar): JString;
    function UnicodeJStringToString(JStr: JString): string;
    function StringToUnicodeJString(const AString: PAnsiChar): JString;

    // JNIEnv methods
    function GetVersion: JInt;
    function DefineClass(const Name: PAnsiChar; Loader: JObject; const Buf: PJByte; Len: JSize): JClass;
    function FindClass(const Name: PAnsiChar): JClass;

    // Reflection Support