Keep par0dy with a3270

lib3270j/src/test/java/org/lib3270j/datastream/DataStreamProcessorTest.java

@@ -66,4 +66,20 @@ public class DataStreamProcessorTest {
             assertEquals('A', screen.getCell(i).ucs4, "Cell " + i + " should be 'A'");
         }
     }
+
+    @Test
+    public void testReadBufferPropagatesLastAid() {
+        org.lib3270j.input.InputProcessor input = new org.lib3270j.input.InputProcessor(screen, translator, null);
+        processor.setInputProcessor(input);
+        input.setLastAid(AID_ENTER);
+
+        java.util.concurrent.atomic.AtomicReference<byte[]> sentData = new java.util.concurrent.atomic.AtomicReference<>();
+        processor.setOutputCallback(sentData::set);
+
+        byte[] rbRecord = new byte[] { (byte) CMD_RB };
+        processor.processRecord(rbRecord, 0, rbRecord.length, true);
+
+        assertNotNull(sentData.get());
+        assertEquals((byte) AID_ENTER, sentData.get()[0], "ReadBuffer must transmit operator's stored AID");
+    }
 }

lib3270j/src/test/java/org/lib3270j/input/InputProcessorTest.java

@@ -153,4 +153,50 @@ public class InputProcessorTest {
         assertEquals((byte) 0xFF, sf[34]);
         assertEquals((byte) AID_ENTER, sf[35]);
     }
+
+    @Test
+    public void testSendAidSuppressesNullsInModifiedField() {
+        java.util.concurrent.atomic.AtomicReference<byte[]> sent = new java.util.concurrent.atomic.AtomicReference<>();
+        InputProcessor input = new InputProcessor(screen, translator, null) {
+            @Override
+            public void sendAid(int aidCode) {
+                // Call super logic by hooking via fake FSM or overriding sendAid
+                super.sendAid(aidCode);
+            }
+        };
+        // Setup screen: field attribute at 0 (unprotected, modified)
+        screen.erase(false);
+        screen.setCellFA(0, (byte) (FA_PRINTABLE | FA_MODIFY));
+        // Pos 1 = null (0x00)
+        screen.getCell(1).ec = 0x00;
+        // Pos 2 = 'Q' (0xD8)
+        screen.getCell(2).ec = (byte) 0xD8;
+        // Pos 3 = 'U' (0xE4)
+        screen.getCell(3).ec = (byte) 0xE4;
+        // Pos 4 = 'I' (0xC9)
+        screen.getCell(4).ec = (byte) 0xC9;
+        // Pos 5 = 'T' (0xE3)
+        screen.getCell(5).ec = (byte) 0xE3;
+        // Next field at 10 (protected)
+        screen.setCellFA(10, (byte) (FA_PRINTABLE | FA_PROTECT));
+
+        // Use custom callback or inspection
+        // Let's verify DataStreamProcessor ReadModified behavior with the same buffer
+        DataStreamProcessor dsp = new DataStreamProcessor(screen, translator);
+        dsp.setInputProcessor(input);
+        dsp.setOutputCallback(sent::set);
+
+        byte[] rmRecord = new byte[] { (byte) CMD_RM };
+        dsp.processRecord(rmRecord, 0, rmRecord.length, true);
+
+        byte[] result = sent.get();
+        assertNotNull(result);
+        // Result format: AID (1 byte), Cursor (2 bytes), SBA (1 byte), Addr (2 bytes), Data ('Q', 'U', 'I', 'T' - 4 bytes)
+        assertEquals(10, result.length, "Result should be AID(1) + Cursor(2) + SBA(1) + Addr(2) + Data(4)");
+        assertEquals((byte) ORDER_SBA, result[3]);
+        assertEquals((byte) 0xD8, result[6]); // 'Q'
+        assertEquals((byte) 0xE4, result[7]); // 'U'
+        assertEquals((byte) 0xC9, result[8]); // 'I'
+        assertEquals((byte) 0xE3, result[9]); // 'T'
+    }
 }