com.foxit.sdk.pdf.SignatureCallback Class Reference

Public Member Functions

int continueCalcDigest (java.lang.Object client_data, PauseCallback pause)
 A callback function used to continue the custom digest calculation process.
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boolean isNeedPadData ()
 Check whether to return all contents with padding zero or not, when callback function SignatureCallback.verifySigState is called.
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void release ()
 A callback function used to release current callback object itself.
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boolean startCalcDigest (FileReaderCallback file, int[] byte_range_array, Signature signature, java.lang.Object client_data)
 A callback function used to start a custom digest calculation, mainly to initialize the calculation process.
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int verifySigState (byte[] digest, byte[] signed_data, java.lang.Object client_data)
 A callback function used to do verifying and return the verify state.
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Detailed Description

This class represent a callback object to sign or verify signature. All the pure virtual functions in this class are used as callback functions and should be implemented by user, in order to sign or verify signature in a customized way.
User can set register customized signature callback object to Foxit PDF SDK by function common.Library.registerSignatureCallback with filter and sub filter as the callback name.

See also
com.foxit.sdk.common.Library

Member Function Documentation

◆ continueCalcDigest()

int com.foxit.sdk.pdf.SignatureCallback.continueCalcDigest ( java.lang.Object  client_data,
PauseCallback  pause 
)

A callback function used to continue the custom digest calculation process.

Parameters
[in]pausePause object which decides if the calculation process needs to be paused. If this is NULL, it means not to pause during the calculation process. If this is not NULL, please check the the return value of function NeedToPauseNow() of this input parameter and decide when to pause the calculation process.
[in]client_dataA user-defined object, which is passed by user from function Signature.startSign or Signature.startVerify .
Returns
com.foxit.sdk.common.Progressive.e_Finished means the rendering is finished successfully.
com.foxit.sdk.common.Progressive.e_ToBeContinued means the calculation process is not finished yet and callback function SignatureCallback.continueCalcDigest would be triggered again to continue the process.
com.foxit.sdk.common.Progressive.e_Error means any error occurs.

◆ isNeedPadData()

boolean com.foxit.sdk.pdf.SignatureCallback.isNeedPadData ( )

Check whether to return all contents with padding zero or not, when callback function SignatureCallback.verifySigState is called.

Returns
true means to return all data in contents steam (including padding zero), while false means to return contents data without padding zero in stream end.

◆ release()

void com.foxit.sdk.pdf.SignatureCallback.release ( )

A callback function used to release current callback object itself.

Returns
None.

◆ startCalcDigest()

boolean com.foxit.sdk.pdf.SignatureCallback.startCalcDigest ( FileReaderCallback  file,
int []  byte_range_array,
Signature  signature,
java.lang.Object  client_data 
)

A callback function used to start a custom digest calculation, mainly to initialize the calculation process.

Parameters
[in]fileWhen signing a signature, this represents the source file object to be signed.
When verifying a signature field, this represents the source file object to be verified.
[in]byte_range_arrayA byte range array of the signed document(not the source document).
Elements in this array always be in pairs of offset-size values in order of: offset,size,offset,size...
[in]signatureA signature object.
[in]client_dataA user-defined object, which is passed by user from function Signature.startSign or Signature.startVerify .
Returns
true means the calculation process is successfully started and then SignatureCallback.continueCalcDigest will be triggered to continue the calculation process. false means fail to start a calculation process.

◆ verifySigState()

int com.foxit.sdk.pdf.SignatureCallback.verifySigState ( byte []  digest,
byte []  signed_data,
java.lang.Object  client_data 
)

A callback function used to do verifying and return the verify state.

Host application provides this callback function for custom sign mechanism. This callback function would be triggered during the signature verifying process.

Parameters
[in]digestThe digest data buffer, for source file buffer to be verified.
[in]signed_dataThe signed data buffer.
[in]client_dataA user-defined object, which is passed by user from function Signature.startSign or Signature.startVerify .
Returns
Verify state. Please refer to values starting from com.foxit.sdk.pdf.Signature.e_StateVerifyValid and this should be one or a combination of them.