Fix gradle and add workflows

lib3270j/src/main/java/org/lib3270j/Telnet3270Client.java

@@ -196,6 +196,18 @@ public class Telnet3270Client {
     public void tab()         { inputProcessor.tab(); }
     /** Back-tab to previous unprotected field. */
     public void backTab()     { inputProcessor.backTab(); }
+    /** Move cursor to next line. */
+    public void newline()     { inputProcessor.newline(); }
+    /** Erase all unprotected fields. */
+    public void eraseInput()  { inputProcessor.eraseInput(); }
+    /** Insert Duplicate order. */
+    public void dup()         { inputProcessor.dup(); }
+    /** Insert Field Mark order. */
+    public void fieldMark()   { inputProcessor.fieldMark(); }
+    /** Attention key. */
+    public void attn()        { inputProcessor.attn(); }
+    /** SysReq key. */
+    public void sysReq()      { inputProcessor.sysReq(); }
     /** Reset (unlock keyboard). */  
     public void reset()       { inputProcessor.reset(); }
 }

lib3270j/src/main/java/org/lib3270j/datastream/DataStreamProcessor.java

@@ -816,8 +816,18 @@ public class DataStreamProcessor {
     }
 
     private void sendRequestedQueryReplies(byte[] codes) {
-        // For now, send all — refinement can come later
-        sendAllQueryReplies();
+        byte[] qr = qrBuilder.buildQueryReplies(codes, screen.getMaxCols(), screen.getMaxRows(),
+                screen.getMaxCols() * screen.getMaxRows());
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < qr.length; i++) {
+            sb.append(String.format("%02x ", qr[i] & 0xFF));
+            if ((i + 1) % 32 == 0)
+                sb.append("\n  ");
+        }
+        log.info("Requested query reply (" + qr.length + " bytes):\n  " + sb.toString().trim());
+        if (outputSender != null) {
+            outputSender.send3270Data(qr);
+        }
     }
 
     // ========== Output helpers ==========

lib3270j/src/main/java/org/lib3270j/datastream/QueryReplyBuilder.java

@@ -70,13 +70,69 @@ public class QueryReplyBuilder {
         appendQueryReply(out, QR_REPLY_MODES, buildReplyModes());
 
         // Distributed Data Management (DFT File Transfer)
-        // Hardcoded limit of 4096 is standard; the client can configure it during transfer.
         appendQueryReply(out, QR_DDM, buildDdm(4096));
 
         // Implicit Partition
         appendQueryReply(out, QR_IMP_PART, buildImplicitPartition(maxCols, maxRows));
 
-        log.info("Built " + out.size() + " bytes of query replies");
+        log.info("Built " + out.size() + " bytes of all query replies");
+        return out.toByteArray();
+    }
+
+    /**
+     * Build specific query replies in response to a Read Partition Query List (SF_RPQ_LIST).
+     * For any unsupported requested query code, emits a QR_NULL (0xFF) structured field
+     * matching x3270 sf.c behavior.
+     */
+    public byte[] buildQueryReplies(byte[] requestedCodes, int maxCols, int maxRows, int bufferSize) {
+        if (requestedCodes == null || requestedCodes.length == 0) {
+            return buildAllQueryReplies(maxCols, maxRows, bufferSize);
+        }
+
+        ByteArrayOutputStream out = new ByteArrayOutputStream(512);
+        out.write(AID_SF);
+
+        for (byte codeByte : requestedCodes) {
+            int code = codeByte & 0xFF;
+            switch (code) {
+                case QR_SUMMARY:
+                    appendQueryReply(out, QR_SUMMARY, buildSummary());
+                    break;
+                case QR_USABLE_AREA:
+                    appendQueryReply(out, QR_USABLE_AREA, buildUsableArea(maxCols, maxRows, bufferSize));
+                    break;
+                case QR_ALPHA_PART:
+                    appendQueryReply(out, QR_ALPHA_PART, buildAlphaPartitions(maxRows));
+                    break;
+                case QR_CHARSETS:
+                    appendQueryReply(out, QR_CHARSETS, buildCharsets());
+                    break;
+                case QR_COLOR:
+                    appendQueryReply(out, QR_COLOR, buildColor());
+                    break;
+                case QR_HIGHLIGHTING:
+                    appendQueryReply(out, QR_HIGHLIGHTING, buildHighlighting());
+                    break;
+                case QR_REPLY_MODES:
+                    appendQueryReply(out, QR_REPLY_MODES, buildReplyModes());
+                    break;
+                case QR_DDM:
+                    appendQueryReply(out, QR_DDM, buildDdm(4096));
+                    break;
+                case QR_IMP_PART:
+                    appendQueryReply(out, QR_IMP_PART, buildImplicitPartition(maxCols, maxRows));
+                    break;
+                case QR_RPQNAMES:
+                    appendQueryReply(out, QR_RPQNAMES, new byte[0]);
+                    break;
+                default:
+                    // Unsupported query reply code — emit QR_NULL
+                    appendQueryReply(out, QR_NULL, new byte[0]);
+                    break;
+            }
+        }
+
+        log.info("Built " + out.size() + " bytes of requested query replies for " + requestedCodes.length + " codes");
         return out.toByteArray();
     }
 

lib3270j/src/main/java/org/lib3270j/ft/FTConfig.java

@@ -225,84 +225,96 @@ public class FTConfig {
         // IND$FILE GET/PUT hostfile
         cmd.append("IND$FILE ");
         cmd.append(isReceive() ? "GET " : "PUT ");
-        cmd.append(hostFilename);
+        cmd.append(hostFilename != null ? hostFilename.trim() : "");
 
-        // CMS/CICS options use ( prefix
-        if (hostType != HostType.TSO) {
-            cmd.append(" (");
-        } else {
-            cmd.append(" ");
-        }
+        // Collect options into a separate buffer
+        StringBuilder opts = new StringBuilder();
 
         // Mode
         if (isAscii()) {
-            cmd.append("ASCII");
+            opts.append("ASCII");
         } else if (hostType == HostType.CICS) {
-            cmd.append("BINARY");
+            opts.append("BINARY");
         }
 
         // CR/LF handling
         if (isAscii() && isCrFlag()) {
-            cmd.append(" CRLF");
-        } else if (hostType == HostType.CICS) {
-            cmd.append(" NOCRLF");
+            if (opts.length() > 0) opts.append(" ");
+            opts.append("CRLF");
+        } else if (hostType == HostType.CICS && !isAscii()) {
+            if (opts.length() > 0) opts.append(" ");
+            opts.append("NOCRLF");
         }
 
         // Append (send only)
         if (isAppend() && isSend()) {
-            cmd.append(" APPEND");
+            if (opts.length() > 0) opts.append(" ");
+            opts.append("APPEND");
         }
 
-        // TSO-specific send options
+        // Host-specific send options
         if (isSend()) {
             if (hostType == HostType.TSO) {
                 if (recfm != RecordFormat.DEFAULT) {
-                    cmd.append(" RECFM(");
+                    if (opts.length() > 0) opts.append(" ");
+                    opts.append("RECFM(");
                     switch (recfm) {
-                        case FIXED:     cmd.append("F"); break;
-                        case VARIABLE:  cmd.append("V"); break;
-                        case UNDEFINED: cmd.append("U"); break;
+                        case FIXED:     opts.append("F"); break;
+                        case VARIABLE:  opts.append("V"); break;
+                        case UNDEFINED: opts.append("U"); break;
                         default: break;
                     }
-                    cmd.append(")");
+                    opts.append(")");
                     if (lrecl > 0) {
-                        cmd.append(" LRECL(").append(lrecl).append(")");
+                        opts.append(" LRECL(").append(lrecl).append(")");
                     }
                     if (blksize > 0) {
-                        cmd.append(" BLKSIZE(").append(blksize).append(")");
+                        opts.append(" BLKSIZE(").append(blksize).append(")");
                     }
                 }
                 if (units != AllocationUnit.DEFAULT) {
-                    cmd.append(" SPACE(").append(primarySpace);
+                    if (opts.length() > 0) opts.append(" ");
+                    opts.append("SPACE(").append(primarySpace);
                     if (secondarySpace > 0) {
-                        cmd.append(",").append(secondarySpace);
+                        opts.append(",").append(secondarySpace);
                     }
-                    cmd.append(")");
+                    opts.append(")");
                     switch (units) {
-                        case TRACKS:    cmd.append(" TRACKS"); break;
-                        case CYLINDERS: cmd.append(" CYLINDERS"); break;
-                        case AVBLOCK:   cmd.append(" AVBLOCK(").append(avblock).append(")"); break;
+                        case TRACKS:    opts.append(" TRACKS"); break;
+                        case CYLINDERS: opts.append(" CYLINDERS"); break;
+                        case AVBLOCK:   opts.append(" AVBLOCK(").append(avblock).append(")"); break;
                         default: break;
                     }
                 }
             } else if (hostType == HostType.CMS) {
                 if (recfm != RecordFormat.DEFAULT) {
-                    cmd.append(" RECFM ");
+                    if (opts.length() > 0) opts.append(" ");
+                    opts.append("RECFM ");
                     switch (recfm) {
-                        case FIXED:    cmd.append("F"); break;
-                        case VARIABLE: cmd.append("V"); break;
+                        case FIXED:    opts.append("F"); break;
+                        case VARIABLE: opts.append("V"); break;
                         default: break;
                     }
                     if (lrecl > 0) {
-                        cmd.append(" LRECL ").append(lrecl);
+                        opts.append(" LRECL ").append(lrecl);
                     }
                 }
             }
         }
 
         // Additional options
-        if (otherOptions != null) {
-            cmd.append(" ").append(otherOptions);
+        if (otherOptions != null && !otherOptions.trim().isEmpty()) {
+            if (opts.length() > 0) opts.append(" ");
+            opts.append(otherOptions.trim());
+        }
+
+        // Apply options with host-specific prefix only if options are present
+        if (opts.length() > 0) {
+            if (hostType != HostType.TSO) {
+                cmd.append(" (").append(opts.toString());
+            } else {
+                cmd.append(" ").append(opts.toString());
+            }
         }
 
         return cmd.toString().trim();

lib3270j/src/main/java/org/lib3270j/ft/FTCut.java

@@ -21,7 +21,7 @@ public class FTCut {
 
     /** Callback for transfer events */
     public interface FTCutListener {
-        void onTransferRunning();
+        void onCutRunning();
         void onTransferComplete(String errorMessage);
         void onTransferAborted(String errorMessage);
         void onBytesTransferred(long bytes);
@@ -221,7 +221,7 @@ public class FTCut {
                 xlateBufIx = 0;
                 cutEof = false;
                 cutAck();
-                listener.onTransferRunning();
+                listener.onCutRunning();
                 break;
 
             case SC_XFER_COMPLETE:

lib3270j/src/main/java/org/lib3270j/ft/FTDft.java

@@ -23,7 +23,7 @@ public class FTDft {
 
     /** Callback for transfer events (shared interface with CUT) */
     public interface FTDftListener {
-        void onTransferRunning();
+        void onDftRunning();
         void onTransferComplete(String errorMessage);
         void onTransferAborted(String errorMessage);
         void onBytesTransferred(long bytes);
@@ -178,7 +178,7 @@ public class FTDft {
             log.info("DFT: Open request for message stream");
         } else {
             messageFlag = false;
-            listener.onTransferRunning();
+            listener.onDftRunning();
         }
 
         dftEof = false;

lib3270j/src/main/java/org/lib3270j/input/InputProcessor.java

@@ -4,6 +4,7 @@ import org.lib3270j.screen.ScreenBuffer;
 import org.lib3270j.screen.ExtendedAttribute;
 import org.lib3270j.charset.EbcdicTranslator;
 import org.lib3270j.telnet.TelnetFSM;
+import org.lib3270j.protocol.TelnetConstants;
 import static org.lib3270j.protocol.DS3270Constants.*;
 
 import java.io.ByteArrayOutputStream;
@@ -362,6 +363,82 @@ public class InputProcessor {
         deleteChar();
     }
 
+    /** Erase All Unprotected fields (Erase Input key in 3270). */
+    public void eraseInput() {
+        if (keyboardLocked) return;
+        screen.eraseAllUnprotected();
+        screen.markAllChanged();
+    }
+
+    /** Move cursor to first unprotected field on next line (Newline key in 3270). */
+    public void newline() {
+        if (keyboardLocked) return;
+        int cur = screen.getCursorAddress();
+        int cols = screen.getCols();
+        int rows = screen.getRows();
+        int curRow = cur / cols;
+        int nextRow = (curRow + 1) % rows;
+        int target = nextRow * cols;
+        if (screen.isFormatted()) {
+            target = screen.findNextUnprotected(target == 0 ? (rows * cols - 1) : (target - 1));
+        }
+        screen.setCursorAddress(target);
+        screen.markAllChanged();
+    }
+
+    /** Insert Duplicate (DUP) code and advance to next field. */
+    public void dup() {
+        if (keyboardLocked) return;
+        int baddr = screen.getCursorAddress();
+        byte faVal = screen.getFieldAttributeAt(baddr);
+        if (faIsProtected(faVal & 0xFF)) return;
+
+        ExtendedAttribute ea = screen.getCell(baddr);
+        ea.ec = (byte) FCORDER_DUP;
+        ea.ucs4 = '*';
+        int faAddr = screen.findFieldAttribute(baddr);
+        if (faAddr >= 0) {
+            screen.getCell(faAddr).fa = (byte) (screen.getCell(faAddr).fa | FA_MODIFY);
+        }
+        tab();
+    }
+
+    /** Insert Field Mark (FM) code. */
+    public void fieldMark() {
+        if (keyboardLocked) return;
+        int baddr = screen.getCursorAddress();
+        byte faVal = screen.getFieldAttributeAt(baddr);
+        if (faIsProtected(faVal & 0xFF)) return;
+
+        ExtendedAttribute ea = screen.getCell(baddr);
+        ea.ec = (byte) FCORDER_FM;
+        ea.ucs4 = ';';
+        int faAddr = screen.findFieldAttribute(baddr);
+        if (faAddr >= 0) {
+            screen.getCell(faAddr).fa = (byte) (screen.getCell(faAddr).fa | FA_MODIFY);
+        }
+        int size = screen.getRows() * screen.getCols();
+        baddr = (baddr + 1) % size;
+        while (screen.getCell(baddr).isFieldAttribute()) {
+            baddr = (baddr + 1) % size;
+        }
+        screen.setCursorAddress(baddr);
+        screen.markAllChanged();
+    }
+
+    /** Attention key (sends Telnet IP). */
+    public void attn() {
+        if (fsm != null && fsm.getConnectionState() != null && fsm.getConnectionState().isConnected()) {
+            byte[] ip = new byte[] { (byte) TelnetConstants.IAC, (byte) TelnetConstants.IP };
+            fsm.sendRecord(ip);
+        }
+    }
+
+    /** SysReq key. */
+    public void sysReq() {
+        reset();
+    }
+
     /** Reset (unlock keyboard, cancel insert mode). */
     public void reset() {
         setKeyboardLocked(false);

lib3270j/src/main/java/org/lib3270j/screen/ScreenBuffer.java

@@ -305,6 +305,7 @@ public class ScreenBuffer {
 
     private char getAplGraphic(int ec) {
         switch (ec) {
+            // Box-drawing line and corner characters (standard IBM 3270 GE / APL)
             case 0xA2: return '\u2500'; // Horizontal Line 's' -> '─'
             case 0x85: return '\u2502'; // Vertical Line 'e' -> '│'
             case 0xC5: return '\u250C'; // Top Left 'E' -> '┌'
@@ -316,6 +317,24 @@ public class ScreenBuffer {
             case 0xC7: return '\u252C'; // T-Junction Top 'G' -> '┬'
             case 0xD7: return '\u2534'; // T-Junction Bottom 'P' -> '┴'
             case 0xCB: return '\u253C'; // Cross -> '┼'
+
+            // Special math and APL symbols (matching x3270 cg.c / apl.c)
+            case 0x8C: return '\u2264'; // Less-than or equal '≤'
+            case 0xAE: return '\u2265'; // Greater-than or equal '≥'
+            case 0xBE: return '\u2260'; // Not equal '≠'
+            case 0xAD: return '[';      // Left bracket
+            case 0xBD: return ']';      // Right bracket
+            case 0x8D: return '{';      // Left brace
+            case 0x9D: return '}';      // Right brace
+            case 0xB0: return '\u00B0'; // Degree '°'
+            case 0xB1: return '\u00B1'; // Plus-minus '±'
+            case 0xB2: return '\u00B2'; // Superscript 2 '²'
+            case 0xB3: return '\u00B3'; // Superscript 3 '³'
+            case 0xAF: return '\u00AF'; // Overbar '¯'
+            case 0xBA: return '\u03A9'; // Omega 'Ω'
+            case 0xBF: return '\u00B5'; // Micro 'µ'
+            case 0x5F: return '\u00AC'; // Not sign '¬'
+
             default: return translator.ebcdicToUnicode(ec);
         }
     }

lib3270j/src/main/java/org/lib3270j/telnet/TelnetConnection.java

@@ -37,13 +37,26 @@ public class TelnetConnection {
      * Connect to the host. Blocks until connection is established or fails.
      */
     public void connect() throws IOException {
-        log.info("Connecting to " + config.getHost() + ":" + config.getPort());
-        socket = new Socket();
-        socket.setKeepAlive(true);
-        socket.setOOBInline(true);
-        socket.setTcpNoDelay(true);
-        socket.connect(new InetSocketAddress(config.getHost(), config.getPort()),
-                       config.getConnectTimeoutMs());
+        if (config.isUseTls()) {
+            log.info("Connecting with TLS to " + config.getHost() + ":" + config.getPort());
+            javax.net.ssl.SSLSocketFactory ssf = (javax.net.ssl.SSLSocketFactory) javax.net.ssl.SSLSocketFactory.getDefault();
+            javax.net.ssl.SSLSocket sslSocket = (javax.net.ssl.SSLSocket) ssf.createSocket();
+            sslSocket.setKeepAlive(true);
+            sslSocket.setOOBInline(true);
+            sslSocket.setTcpNoDelay(true);
+            sslSocket.connect(new InetSocketAddress(config.getHost(), config.getPort()),
+                           config.getConnectTimeoutMs());
+            sslSocket.startHandshake();
+            socket = sslSocket;
+        } else {
+            log.info("Connecting to " + config.getHost() + ":" + config.getPort());
+            socket = new Socket();
+            socket.setKeepAlive(true);
+            socket.setOOBInline(true);
+            socket.setTcpNoDelay(true);
+            socket.connect(new InetSocketAddress(config.getHost(), config.getPort()),
+                           config.getConnectTimeoutMs());
+        }
 
         inputStream = new BufferedInputStream(socket.getInputStream(), READ_BUFFER_SIZE);
         outputStream = new BufferedOutputStream(socket.getOutputStream());

lib3270j/src/test/java/org/lib3270j/charset/EbcdicTranslatorTest.java

@@ -0,0 +1,66 @@
+package org.lib3270j.charset;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class EbcdicTranslatorTest {
+
+    private final EbcdicTranslator translator = new EbcdicTranslator();
+
+    @Test
+    public void testBasicAlphanumericTranslation() {
+        assertEquals('A', translator.ebcdicToUnicode(0xC1));
+        assertEquals('B', translator.ebcdicToUnicode(0xC2));
+        assertEquals('Z', translator.ebcdicToUnicode(0xE9));
+        assertEquals('a', translator.ebcdicToUnicode(0x81));
+        assertEquals('z', translator.ebcdicToUnicode(0xA9));
+        assertEquals('0', translator.ebcdicToUnicode(0xF0));
+        assertEquals('9', translator.ebcdicToUnicode(0xF9));
+        assertEquals(' ', translator.ebcdicToUnicode(0x40));
+    }
+
+    @Test
+    public void testReverseTranslation() {
+        assertEquals(0xC1, translator.unicodeToEbcdic('A'));
+        assertEquals(0x81, translator.unicodeToEbcdic('a'));
+        assertEquals(0xF0, translator.unicodeToEbcdic('0'));
+        assertEquals(0x40, translator.unicodeToEbcdic(' '));
+        assertEquals(0x4B, translator.unicodeToEbcdic('.'));
+        assertEquals(0x6B, translator.unicodeToEbcdic(','));
+    }
+
+    @Test
+    public void testSpecialCharactersCP037() {
+        // [ and ]
+        assertEquals(0xBA, translator.unicodeToEbcdic('['));
+        assertEquals(0xBB, translator.unicodeToEbcdic(']'));
+        assertEquals('[', translator.ebcdicToUnicode(0xBA));
+        assertEquals(']', translator.ebcdicToUnicode(0xBB));
+
+        // { and }
+        assertEquals(0xC0, translator.unicodeToEbcdic('{'));
+        assertEquals(0xD0, translator.unicodeToEbcdic('}'));
+        assertEquals('{', translator.ebcdicToUnicode(0xC0));
+        assertEquals('}', translator.ebcdicToUnicode(0xD0));
+
+        // Backslash \
+        assertEquals(0xE0, translator.unicodeToEbcdic('\\'));
+        assertEquals('\\', translator.ebcdicToUnicode(0xE0));
+
+        // Caret ^
+        assertEquals(0xB0, translator.unicodeToEbcdic('^'));
+        assertEquals('^', translator.ebcdicToUnicode(0xB0));
+
+        // Tilde ~
+        assertEquals(0xA1, translator.unicodeToEbcdic('~'));
+        assertEquals('~', translator.ebcdicToUnicode(0xA1));
+    }
+
+    @Test
+    public void testStringRoundTrip() {
+        String test = "Hello World! 123 [TEST] {VAR} \\";
+        byte[] ebcdic = translator.stringToEbcdic(test);
+        String restored = translator.ebcdicToString(ebcdic, 0, ebcdic.length);
+        assertEquals(test, restored);
+    }
+}

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

@@ -0,0 +1,69 @@
+package org.lib3270j.datastream;
+
+import org.junit.jupiter.api.Test;
+import org.lib3270j.TerminalModel;
+import org.lib3270j.charset.EbcdicTranslator;
+import org.lib3270j.screen.ScreenBuffer;
+import org.lib3270j.screen.ExtendedAttribute;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.lib3270j.protocol.DS3270Constants.*;
+
+public class DataStreamProcessorTest {
+
+    private final EbcdicTranslator translator = new EbcdicTranslator();
+    private final ScreenBuffer screen = new ScreenBuffer(TerminalModel.IBM_3279_4, translator);
+    private final DataStreamProcessor processor = new DataStreamProcessor(screen, translator);
+
+    @Test
+    public void testEraseWriteAndSBAOrder() {
+        // Build an EW record:
+        // Byte 0: CMD_EW (0x05)
+        // Byte 1: WCC (0xC3) - restore keyboard, reset MDT
+        // Byte 2: ORDER_SBA (0x11)
+        // Byte 3, 4: Encoded address for 0 (0x40, 0x40)
+        // Byte 5: ORDER_SF (0x1D)
+        // Byte 6: FA (0xC0) - unprotected
+        // Byte 7..11: EBCDIC "HELLO" (0xC8, 0xC5, 0xD3, 0xD3, 0xD6)
+        byte[] record = new byte[] {
+            (byte) CMD_EW,
+            (byte) 0xC3,
+            (byte) ORDER_SBA,
+            (byte) 0x40, (byte) 0x40,
+            (byte) ORDER_SF,
+            (byte) FA_PRINTABLE,
+            (byte) 0xC8, (byte) 0xC5, (byte) 0xD3, (byte) 0xD3, (byte) 0xD6
+        };
+
+        processor.processRecord(record, 0, record.length, true);
+
+        assertTrue(screen.isFormatted());
+        assertTrue(screen.getCell(0).isFieldAttribute());
+
+        // Positions 1..5 should contain "HELLO"
+        assertEquals('H', screen.getCell(1).ucs4);
+        assertEquals('E', screen.getCell(2).ucs4);
+        assertEquals('L', screen.getCell(3).ucs4);
+        assertEquals('L', screen.getCell(4).ucs4);
+        assertEquals('O', screen.getCell(5).ucs4);
+    }
+
+    @Test
+    public void testRepeatToAddressOrder() {
+        // Write record with RA from 0 to 10 with character 'A' (0xC1)
+        byte[] record = new byte[] {
+            (byte) CMD_EW,
+            (byte) 0xC3,
+            (byte) ORDER_SBA,
+            (byte) 0x40, (byte) 0x40, // Address 0
+            (byte) ORDER_RA,
+            (byte) 0x40, (byte) 0x4A, // Address 10 (0x40, 0x4A)
+            (byte) 0xC1              // EBCDIC 'A'
+        };
+
+        processor.processRecord(record, 0, record.length, true);
+
+        for (int i = 0; i < 10; i++) {
+            assertEquals('A', screen.getCell(i).ucs4, "Cell " + i + " should be 'A'");
+        }
+    }
+}

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

@@ -0,0 +1,55 @@
+package org.lib3270j.datastream;
+
+import org.junit.jupiter.api.Test;
+import org.lib3270j.TerminalModel;
+import org.lib3270j.charset.EbcdicTranslator;
+import org.lib3270j.screen.ScreenBuffer;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.lib3270j.protocol.DS3270Constants.*;
+
+public class QueryReplyBuilderTest {
+
+    private final EbcdicTranslator translator = new EbcdicTranslator();
+    private final ScreenBuffer screen = new ScreenBuffer(TerminalModel.IBM_3279_4, translator);
+    private final QueryReplyBuilder qrBuilder = new QueryReplyBuilder(screen);
+
+    @Test
+    public void testBuildAllQueryReplies() {
+        byte[] replies = qrBuilder.buildAllQueryReplies(80, 43, 80 * 43);
+        assertNotNull(replies);
+        assertTrue(replies.length > 0);
+        assertEquals((byte) AID_SF, replies[0]);
+    }
+
+    @Test
+    public void testBuildFilteredQueryRepliesWithSupportedCodes() {
+        byte[] requested = new byte[] { (byte) QR_DDM, (byte) QR_USABLE_AREA };
+        byte[] replies = qrBuilder.buildQueryReplies(requested, 80, 43, 80 * 43);
+
+        assertNotNull(replies);
+        assertEquals((byte) AID_SF, replies[0]);
+
+        // First SF should be DDM: length (2 bytes), SFID_QREPLY (0x81), QR_DDM (0x95)
+        int len1 = ((replies[1] & 0xFF) << 8) | (replies[2] & 0xFF);
+        assertEquals(0x81, replies[3] & 0xFF);
+        assertEquals(QR_DDM, replies[4] & 0xFF);
+
+        // Second SF should be Usable Area
+        int pos2 = 1 + len1;
+        int len2 = ((replies[pos2] & 0xFF) << 8) | (replies[pos2 + 1] & 0xFF);
+        assertEquals(0x81, replies[pos2 + 2] & 0xFF);
+        assertEquals(QR_USABLE_AREA, replies[pos2 + 3] & 0xFF);
+    }
+
+    @Test
+    public void testBuildFilteredQueryRepliesWithUnsupportedCode() {
+        byte[] requested = new byte[] { (byte) 0x77 }; // Unsupported code
+        byte[] replies = qrBuilder.buildQueryReplies(requested, 80, 43, 80 * 43);
+
+        assertNotNull(replies);
+        assertEquals((byte) AID_SF, replies[0]);
+        // Should emit QR_NULL (0xFF)
+        assertEquals(0x81, replies[3] & 0xFF);
+        assertEquals(QR_NULL, replies[4] & 0xFF);
+    }
+}

lib3270j/src/test/java/org/lib3270j/ft/FTConfigTest.java

@@ -0,0 +1,83 @@
+package org.lib3270j.ft;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+public class FTConfigTest {
+
+    @Test
+    public void testTsoReceiveAscii() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.TSO);
+        config.setDirection(FTConfig.Direction.RECEIVE);
+        config.setHostFilename("MY.DATASET");
+        config.setTransferMode(FTConfig.TransferMode.ASCII);
+        config.setCrAction(FTConfig.CrAction.REMOVE);
+
+        assertEquals("IND$FILE GET MY.DATASET ASCII CRLF", config.buildCommand());
+    }
+
+    @Test
+    public void testTsoReceiveBinary() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.TSO);
+        config.setDirection(FTConfig.Direction.RECEIVE);
+        config.setHostFilename("'USER.BIN.DATA'");
+        config.setTransferMode(FTConfig.TransferMode.BINARY);
+
+        assertEquals("IND$FILE GET 'USER.BIN.DATA'", config.buildCommand());
+    }
+
+    @Test
+    public void testTsoSendFixedRecfm() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.TSO);
+        config.setDirection(FTConfig.Direction.SEND);
+        config.setHostFilename("MY.DATASET");
+        config.setTransferMode(FTConfig.TransferMode.ASCII);
+        config.setCrAction(FTConfig.CrAction.REMOVE);
+        config.setRecfm("F");
+        config.setLrecl("80");
+        config.setBlksize("3120");
+
+        assertEquals("IND$FILE PUT MY.DATASET ASCII CRLF RECFM(F) LRECL(80) BLKSIZE(3120)", config.buildCommand());
+    }
+
+    @Test
+    public void testCmsReceiveBinaryNoNakedParen() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.CMS);
+        config.setDirection(FTConfig.Direction.RECEIVE);
+        config.setHostFilename("PROFILE EXEC A");
+        config.setTransferMode(FTConfig.TransferMode.BINARY);
+
+        // In CMS, binary receive has no options, so NO open parenthesis '(' should be generated!
+        assertEquals("IND$FILE GET PROFILE EXEC A", config.buildCommand());
+    }
+
+    @Test
+    public void testCmsReceiveAscii() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.CMS);
+        config.setDirection(FTConfig.Direction.RECEIVE);
+        config.setHostFilename("TEST DATA A");
+        config.setTransferMode(FTConfig.TransferMode.ASCII);
+        config.setCrAction(FTConfig.CrAction.REMOVE);
+
+        assertEquals("IND$FILE GET TEST DATA A (ASCII CRLF", config.buildCommand());
+    }
+
+    @Test
+    public void testCmsSendWithRecfmAndLrecl() {
+        FTConfig config = new FTConfig();
+        config.setHostType(FTConfig.HostType.CMS);
+        config.setDirection(FTConfig.Direction.SEND);
+        config.setHostFilename("TEST FILE A");
+        config.setTransferMode(FTConfig.TransferMode.ASCII);
+        config.setCrAction(FTConfig.CrAction.REMOVE);
+        config.setRecfm("V");
+        config.setLrecl("132");
+
+        assertEquals("IND$FILE PUT TEST FILE A (ASCII CRLF RECFM V LRECL 132", config.buildCommand());
+    }
+}

lib3270j/src/test/java/org/lib3270j/protocol/DS3270ConstantsTest.java

@@ -0,0 +1,51 @@
+package org.lib3270j.protocol;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.lib3270j.protocol.DS3270Constants.*;
+
+public class DS3270ConstantsTest {
+
+    @Test
+    public void test12BitAddressRoundTrip() {
+        int rows = 24;
+        int cols = 80;
+        int maxAddr = rows * cols; // 1920
+
+        for (int addr = 0; addr < maxAddr; addr += 17) {
+            byte[] encoded = encodeAddress(addr, rows, cols);
+            assertEquals(2, encoded.length);
+            int decoded = decodeAddress(encoded[0] & 0xFF, encoded[1] & 0xFF);
+            assertEquals(addr, decoded, "Address " + addr + " failed round trip");
+        }
+    }
+
+    @Test
+    public void test14BitAddressRoundTrip() {
+        int rows = 60;
+        int cols = 80; // 4800 (> 4096, triggers 14-bit format)
+        int maxAddr = rows * cols;
+
+        for (int addr = 0; addr < maxAddr; addr += 123) {
+            byte[] encoded = encodeAddress(addr, rows, cols);
+            assertEquals(2, encoded.length);
+            int decoded = decodeAddress(encoded[0] & 0xFF, encoded[1] & 0xFF);
+            assertEquals(addr, decoded, "14-bit address " + addr + " failed round trip");
+        }
+    }
+
+    @Test
+    public void testFieldAttributePredicates() {
+        int protectedHighMod = FA_PRINTABLE | FA_PROTECT | FA_INT_HIGH_SEL | FA_MODIFY;
+        assertTrue(faIsProtected(protectedHighMod));
+        assertTrue(faIsHigh(protectedHighMod));
+        assertTrue(faIsModified(protectedHighMod));
+        assertFalse(faIsNumeric(protectedHighMod));
+        assertFalse(faIsSkip(protectedHighMod));
+
+        int skipField = FA_PRINTABLE | FA_PROTECT | FA_NUMERIC;
+        assertTrue(faIsSkip(skipField));
+        assertTrue(faIsProtected(skipField));
+        assertTrue(faIsNumeric(skipField));
+    }
+}

lib3270j/src/test/java/org/lib3270j/screen/ScreenBufferTest.java

@@ -0,0 +1,64 @@
+package org.lib3270j.screen;
+
+import org.junit.jupiter.api.Test;
+import org.lib3270j.TerminalModel;
+import org.lib3270j.charset.EbcdicTranslator;
+import static org.junit.jupiter.api.Assertions.*;
+import static org.lib3270j.protocol.DS3270Constants.*;
+
+public class ScreenBufferTest {
+
+    private final EbcdicTranslator translator = new EbcdicTranslator();
+    private final ScreenBuffer screen = new ScreenBuffer(TerminalModel.IBM_3279_4, translator);
+
+    @Test
+    public void testScreenInitialization() {
+        assertEquals(24, screen.getRows());
+        assertEquals(80, screen.getCols());
+        assertEquals(43, screen.getMaxRows());
+        assertEquals(80, screen.getMaxCols());
+        assertFalse(screen.isFormatted());
+    }
+
+    @Test
+    public void testScreenEraseAlternate() {
+        screen.erase(true);
+        assertTrue(screen.isScreenAlt());
+        assertEquals(43, screen.getRows());
+        assertEquals(80, screen.getCols());
+
+        screen.erase(false);
+        assertFalse(screen.isScreenAlt());
+        assertEquals(24, screen.getRows());
+        assertEquals(80, screen.getCols());
+    }
+
+    @Test
+    public void testFieldNavigationAndFindAttribute() {
+        screen.erase(false);
+        // Place field attribute at position 0 (unprotected)
+        screen.setCellFA(0, (byte) FA_PRINTABLE);
+        // Place field attribute at position 20 (protected)
+        screen.setCellFA(20, (byte) (FA_PRINTABLE | FA_PROTECT));
+
+        assertTrue(screen.isFormatted());
+        assertEquals(0, screen.findFieldAttribute(5));
+        assertEquals(20, screen.findFieldAttribute(25));
+
+        // findNextUnprotected
+        int nextUnprot = screen.findNextUnprotected(0);
+        assertEquals(1, nextUnprot);
+    }
+
+    @Test
+    public void testGraphicEscapeTranslation() {
+        screen.erase(false);
+        // Set cell at position 10 to horizontal line (0xA2) with CS_GE (0x04)
+        ExtendedAttribute ea = screen.getCell(10);
+        ea.ec = (byte) 0xA2;
+        ea.cs = (byte) CS_GE;
+
+        screen.translateToUnicode();
+        assertEquals('\u2500', ea.ucs4); // '─'
+    }
+}