[Java]: Added scaffolding for running OTF example.

Author: mjpt777

examples/java/uk/co/real_logic/sbe/examples/OtfExample.java

@@ -0,0 +1,78 @@
+package uk.co.real_logic.sbe.examples;
+
+import baseline.Car;
+import baseline.MessageHeader;
+import uk.co.real_logic.sbe.codec.java.DirectBuffer;
+import uk.co.real_logic.sbe.ir.Decoder;
+import uk.co.real_logic.sbe.ir.Encoder;
+import uk.co.real_logic.sbe.ir.IntermediateRepresentation;
+import uk.co.real_logic.sbe.xml.IrGenerator;
+import uk.co.real_logic.sbe.xml.MessageSchema;
+import uk.co.real_logic.sbe.xml.XmlSchemaParser;
+
+import java.io.FileInputStream;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+
+public class OtfExample
+{
+ private static final MessageHeader MESSAGE_HEADER = new MessageHeader();
+ private static final Car CAR = new Car();
+ private static final int ACTING_VERSION = 0;
+ private static final int MSG_BUFFER_CAPACITY = 16 * 1024;
+ private static final int SCHEMA_BUFFER_CAPACITY = 16 * 1024;
+
+ public static void main(final String[] args) throws Exception
+ {
+ // Encode up message and schema as if we just got them off the wire.
+ final ByteBuffer encodedSchemaBuffer = ByteBuffer.allocateDirect(SCHEMA_BUFFER_CAPACITY);
+ encodeSchema(encodedSchemaBuffer);
+
+ final ByteBuffer encodedMsgBuffer = ByteBuffer.allocateDirect(MSG_BUFFER_CAPACITY);
+ encodeTestMessage(encodedMsgBuffer);
+
+
+ // Now lets decode the schema IR so we have IR objects.
+ encodedSchemaBuffer.flip();
+ final IntermediateRepresentation ir = decodeIr(encodedSchemaBuffer);
+
+ // Now we have IR we can read the message header
+
+ // Given the message header we can select the appropriate message to decode.
+ }
+
+ private static void encodeSchema(final ByteBuffer buffer)
+ throws Exception
+ {
+ try (final InputStream in = new FileInputStream("examples/resources/TestSchema.xml"))
+ {
+ final MessageSchema schema = XmlSchemaParser.parse(in);
+ final IntermediateRepresentation ir = new IrGenerator().generate(schema);
+ new Encoder(buffer, ir).encode();
+ }
+ }
+
+ private static void encodeTestMessage(final ByteBuffer buffer)
+ {
+ final DirectBuffer directBuffer = new DirectBuffer(buffer);
+
+ int bufferOffset = 0;
+ MESSAGE_HEADER.wrap(directBuffer, bufferOffset, ACTING_VERSION)
+ .blockLength(CAR.blockLength())
+ .templateId(CAR.templateId())
+ .version(CAR.templateVersion());
+
+ bufferOffset += MESSAGE_HEADER.size();
+
+ GeneratedStubExample.encode(CAR, directBuffer, bufferOffset);
+ }
+
+ private static IntermediateRepresentation decodeIr(final ByteBuffer buffer)
+ throws IOException
+ {
+ final Decoder decoder = new Decoder(buffer);
+ return decoder.decode();
+ }
+}