1 files changed, 50 insertions, 0 deletions
diff --git a/pkix/src/main/java/org/spongycastle/cms/CMSProcessableInputStream.java b/pkix/src/main/java/org/spongycastle/cms/CMSProcessableInputStream.java
new file mode 100644
index 00000000..fc644c95
--- /dev/null
+++ b/pkix/src/main/java/org/spongycastle/cms/CMSProcessableInputStream.java
@@ -0,0 +1,50 @@
+package org.spongycastle.cms;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import org.spongycastle.util.io.Streams;
+
+class CMSProcessableInputStream implements CMSProcessable, CMSReadable
+{
+    private InputStream input;
+    private boolean used = false;
+
+    public CMSProcessableInputStream(
+        InputStream input)
+    {
+        this.input = input;
+    }
+
+    public InputStream getInputStream()
+    {
+        checkSingleUsage();
+
+        return input;
+    }
+
+    public void write(OutputStream zOut)
+        throws IOException, CMSException
+    {
+        checkSingleUsage();
+
+        Streams.pipeAll(input, zOut);
+        input.close();
+    }
+
+    public Object getContent()
+    {
+        return getInputStream();
+    }
+
+    private synchronized void checkSingleUsage()
+    {
+        if (used)
+        {
+            throw new IllegalStateException("CMSProcessableInputStream can only be used once");
+        }
+
+        used = true;
+    }
+}