diff --git a/test/lib-test/jdk/test/lib/process/proc/A.java b/test/lib-test/jdk/test/lib/process/proc/A.java
new file mode 100644
index 00000000000..8f80202b697
--- /dev/null
+++ b/test/lib-test/jdk/test/lib/process/proc/A.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+public class A {
+    public static void main(String[] args) throws Exception {
+        B.go();
+    }
+}
diff --git a/test/lib-test/jdk/test/lib/process/proc/B.java b/test/lib-test/jdk/test/lib/process/proc/B.java
new file mode 100644
index 00000000000..ef92b3f77a2
--- /dev/null
+++ b/test/lib-test/jdk/test/lib/process/proc/B.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+public class B {
+    public static void go() {
+        System.out.println("Hello");
+        System.err.println("World");
+    }
+}
diff --git a/test/lib-test/jdk/test/lib/process/proc/Launcher.java b/test/lib-test/jdk/test/lib/process/proc/Launcher.java
new file mode 100644
index 00000000000..857586586c6
--- /dev/null
+++ b/test/lib-test/jdk/test/lib/process/proc/Launcher.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+import jdk.test.lib.process.Proc;
+
+/*
+ * @test
+ * @bug 8305846
+ * @library /test/lib
+ */
+public class Launcher {
+    public static void main(String[] args) throws Exception {
+        Proc.create("A")
+                .compile()
+                .start()
+                .output()
+                .stdoutShouldContain("Hello")
+                .stderrShouldContain("World");
+    }
+}
diff --git a/test/lib/jdk/test/lib/process/Proc.java b/test/lib/jdk/test/lib/process/Proc.java
index 574e5761d03..0c294e465ab 100644
--- a/test/lib/jdk/test/lib/process/Proc.java
+++ b/test/lib/jdk/test/lib/process/Proc.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,6 +23,8 @@
 
 package jdk.test.lib.process;
 
+import jdk.test.lib.compiler.CompilerUtils;
+
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.IOException;
@@ -118,7 +120,11 @@ public class Proc {
     private boolean inheritIO = false;
     private boolean noDump = false;
 
-    private List<String> cp;        // user-provided classpath
+    private boolean addcp;          // user-provided classpath is appended
+    private List<String> cp;        // user-provided classpaths
+
+    private boolean compile;        // compile the program as well
+
     private String clazz;           // Class to launch
     private String debug;           // debug flag, controller will show data
                                     // transfer between procs. If debug is set,
@@ -195,8 +201,7 @@ public class Proc {
         }
         return this;
     }
-    // Sets classpath. If not called, Proc will choose a classpath. If called
-    // with no arg, no classpath will be used. Can be called multiple times.
+    // Sets classpath. Can be called multiple times.
     public Proc cp(String... s) {
         if (cp == null) {
             cp = new ArrayList<>();
@@ -204,6 +209,12 @@ public class Proc {
         cp.addAll(Arrays.asList(s));
         return this;
     }
+    // Adds classpath to defaults. Can be called multiple times.
+    // Once called, addcp is always true.
+    public Proc addcp(String... s) {
+        addcp = true;
+        return cp(s);
+    }
     // Adds a permission to policy. Can be called multiple times.
     // All perm() calls after a series of grant() calls are grouped into
     // a single grant block. perm() calls before any grant() call are grouped
@@ -259,6 +270,34 @@ public class Proc {
         grant.append(v).append(", ");
         return this;
     }
+    // Compile as well
+    public Proc compile() {
+        compile = true;
+        return this;
+    }
+
+    // get full classpath.
+    // 1. Default classpath used if neither cp() or addcp() is called
+    // 2. User provided classpath (can be empty) used if only cp() is called
+    // 3. User provided classpath + default classpath used, otherwise
+    String fullcp() {
+        if (cp == null) {
+            return System.getProperty("test.class.path") + File.pathSeparator +
+                    System.getProperty("test.src.path");
+        } else {
+            var newcp = new ArrayList<>(cp);
+            if (addcp) {
+                newcp.add(System.getProperty("test.class.path"));
+                newcp.add(System.getProperty("test.src.path"));
+            }
+            if (!newcp.isEmpty()) {
+                return newcp.stream().collect(Collectors.joining(File.pathSeparator));
+            } else {
+                return null;
+            }
+        }
+    }
+
     // Starts the proc
     public Proc start() throws IOException {
         List<String> cmd = new ArrayList<>();
@@ -282,18 +321,26 @@ public class Proc {
             }
         }
 
+        var lcp = fullcp();
+        if (lcp != null) {
+            cmd.add("-cp");
+            cmd.add(lcp);
+        }
+
+        if (compile) {
+            boolean comp = CompilerUtils.compile(
+                    Path.of(System.getProperty("test.src"), clazz + ".java"),
+                    Path.of(System.getProperty("test.classes")),
+                    cmd.subList(1, cmd.size()).toArray(new String[0]));
+                        // subList(1): all options added without launcher name
+            if (!comp) {
+                throw new RuntimeException("Compilation error");
+            }
+        }
+
         Collections.addAll(cmd, splitProperty("test.vm.opts"));
         Collections.addAll(cmd, splitProperty("test.java.opts"));
 
-        if (cp == null) {
-            cmd.add("-cp");
-            cmd.add(System.getProperty("test.class.path") + File.pathSeparator +
-                    System.getProperty("test.src.path"));
-        } else if (!cp.isEmpty()) {
-            cmd.add("-cp");
-            cmd.add(cp.stream().collect(Collectors.joining(File.pathSeparator)));
-        }
-
         if (!secprop.isEmpty()) {
             Path p = Path.of(getId("security"));
             try (OutputStream fos = Files.newOutputStream(p);