TSAClient (iText, a Free Java-PDF library 4.2.0 API)

All Known Implementing Classes:

TSAClientBouncyCastle
```
public interface TSAClient
```
Time Stamp Authority client (caller) interface.
Interface used by the PdfPKCS7 digital signature builder to call Time Stamp Authority providing RFC 3161 compliant time stamp token.

Since:

2.1.6

Author:

Martin Brunecky, 07/17/2007

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`byte[]`	`getTimeStampToken(PdfPKCS7 caller, byte[] imprint)`	Get RFC 3161 timeStampToken.
`int`	`getTokenSizeEstimate()`	Get the time stamp token size estimate.

- Method Detail
  - getTokenSizeEstimate
```
int getTokenSizeEstimate()
```
    Get the time stamp token size estimate. Implementation must return value large enough to accomodate the entire token returned by getTimeStampToken() _prior_ to actual getTimeStampToken() call.
    
    Returns:
    
    an estimate of the token size
  - getTimeStampToken
```
byte[] getTimeStampToken(PdfPKCS7 caller,
                         byte[] imprint)
                  throws java.lang.Exception
```
    Get RFC 3161 timeStampToken. Method may return null indicating that timestamp should be skipped.
    
    Parameters:
    
    caller - PdfPKCS7 - calling PdfPKCS7 instance (in case caller needs it)
    
    imprint - byte[] - data imprint to be time-stamped
    
    Returns:
    
    byte[] - encoded, TSA signed data of the timeStampToken
    
    Throws:
    
    java.lang.Exception - - TSA request failed