Added API filter and missing @since tag
diff --git a/ui/org.eclipse.pde.launching/.settings/.api_filters b/ui/org.eclipse.pde.launching/.settings/.api_filters
new file mode 100644
index 0000000..9754cc4
--- /dev/null
+++ b/ui/org.eclipse.pde.launching/.settings/.api_filters
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<component id="org.eclipse.pde.launching" version="2">
+    <resource path="META-INF/MANIFEST.MF">
+        <filter comment="Backported Java 9 work" id="924844039">
+            <message_arguments>
+                <message_argument value="3.7.50"/>
+                <message_argument value="3.7.0"/>
+            </message_arguments>
+        </filter>
+    </resource>
+    <resource path="src/org/eclipse/pde/launching/AbstractPDELaunchConfiguration.java" type="org.eclipse.pde.launching.AbstractPDELaunchConfiguration">
+        <filter comment="Backported Java 9 work" id="1141899266">
+            <message_arguments>
+                <message_argument value="3.8"/>
+                <message_argument value="3.7"/>
+                <message_argument value="updatePDELaunchConfigModuleSystem(boolean)"/>
+            </message_arguments>
+        </filter>
+    </resource>
+</component>
diff --git a/ui/org.eclipse.pde.launching/src/org/eclipse/pde/launching/AbstractPDELaunchConfiguration.java b/ui/org.eclipse.pde.launching/src/org/eclipse/pde/launching/AbstractPDELaunchConfiguration.java
index 86c5eac..3a91e54 100644
--- a/ui/org.eclipse.pde.launching/src/org/eclipse/pde/launching/AbstractPDELaunchConfiguration.java
+++ b/ui/org.eclipse.pde.launching/src/org/eclipse/pde/launching/AbstractPDELaunchConfiguration.java
@@ -42,6 +42,12 @@
 
 	protected File fConfigDir = null;
 
+	/**
+	 * This field will control the addition of argument --add-modules=ALL-SYSTEM in the VM argument
+	 * during PDE launch. This VM argument is required from Java9 onwards for launching non-modular system
+	 * @since 3.8
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
 	public static boolean shouldVMAddModuleSystem = false;
 
 	@Override
@@ -436,7 +442,9 @@
 	}
 
 	/**
+	 * Updates the field shouldVMAddModuleSystem.
 	 * 
+	 * @since 3.8
 	 */
 	public static void updatePDELaunchConfigModuleSystem(boolean java9) {
 		AbstractPDELaunchConfiguration.shouldVMAddModuleSystem = java9;