1 files changed, 35 insertions, 0 deletions
diff --git a/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/PGPDigestCalculator.java b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/PGPDigestCalculator.java
new file mode 100644
index 000000000..32161e08a
--- /dev/null
+++ b/libraries/spongycastle/pg/src/main/java/org/spongycastle/openpgp/operator/PGPDigestCalculator.java
@@ -0,0 +1,35 @@
+package org.spongycastle.openpgp.operator;
+
+import java.io.OutputStream;
+
+public interface PGPDigestCalculator
+{
+    /**
+        * Return the algorithm number representing the digest implemented by
+        * this calculator.
+        *
+        * @return algorithm number
+        */
+    int getAlgorithm();
+
+    /**
+        * Returns a stream that will accept data for the purpose of calculating
+        * a digest. Use org.spongycastle.util.io.TeeOutputStream if you want to accumulate
+        * the data on the fly as well.
+        *
+        * @return an OutputStream
+        */
+    OutputStream getOutputStream();
+
+    /**
+         * Return the digest calculated on what has been written to the calculator's output stream.
+         *
+         * @return a digest.
+         */
+    byte[] getDigest();
+
+    /**
+     * Reset the underlying digest calculator
+     */
+    void reset();
+}