1 files changed, 81 insertions, 0 deletions
diff --git a/src/main/java/com/lowagie/bc/asn1/DEROutputStream.java b/src/main/java/com/lowagie/bc/asn1/DEROutputStream.java
new file mode 100644
index 0000000..457cae4
--- /dev/null
+++ b/src/main/java/com/lowagie/bc/asn1/DEROutputStream.java
@@ -0,0 +1,81 @@
+package com.lowagie.bc.asn1;
+
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+public class DEROutputStream
+    extends FilterOutputStream implements DERTags
+{
+    public DEROutputStream(
+        OutputStream    os)
+    {
+        super(os);
+    }
+
+    private void writeLength(
+        int length)
+        throws IOException
+    {
+        if (length > 127)
+        {
+            int size = 1;
+            int val = length;
+
+            while ((val >>>= 8) != 0)
+            {
+                size++;
+            }
+
+            write((byte)(size | 0x80));
+
+            for (int i = (size - 1) * 8; i >= 0; i -= 8)
+            {
+                write((byte)(length >> i));
+            }
+        }
+        else
+        {
+            write((byte)length);
+        }
+    }
+
+    void writeEncoded(
+        int     tag,
+        byte[]  bytes)
+        throws IOException
+    {
+        write(tag);
+        writeLength(bytes.length);
+        write(bytes);
+    }
+
+    protected void writeNull()
+        throws IOException
+    {
+        write(NULL);
+        write(0x00);
+    }
+
+    public void writeObject(
+        Object    obj)
+        throws IOException
+    {
+        if (obj == null)
+        {
+            writeNull();
+        }
+        else if (obj instanceof DERObject)
+        {
+            ((DERObject)obj).encode(this);
+        }
+        else if (obj instanceof DEREncodable)
+        {
+            ((DEREncodable)obj).getDERObject().encode(this);
+        }
+        else 
+        {
+            throw new IOException("object not DEREncodable");
+        }
+    }
+}