jdk/src/java.base/share/classes/java/lang/ClassLoader.java

@@ -220,10 +220,13 @@
     // The parent class loader for delegation
     // Note: VM hardcoded the offset of this field, thus all new fields
     // must be added *after* it.
     private final ClassLoader parent;
 
+    // class loader name
+    private final String name;
+
     // the unnamed module for this ClassLoader
     private final Module unnamedModule;
 
     /**
      * Encapsulates the set of parallel capable loader types.

@@ -329,18 +332,27 @@
         }
         return p;
     }
 
     private static Void checkCreateClassLoader() {
+        return checkCreateClassLoader(null);
+    }
+
+    private static Void checkCreateClassLoader(String name) {
+        if (name != null && name.isEmpty()) {
+            throw new IllegalArgumentException("name must be non-empty or null");
+        }
+
         SecurityManager security = System.getSecurityManager();
         if (security != null) {
             security.checkCreateClassLoader();
         }
         return null;
     }
 
-    private ClassLoader(Void unused, ClassLoader parent) {
+    private ClassLoader(Void unused, String name, ClassLoader parent) {
+        this.name = name;
         this.parent = parent;
         this.unnamedModule
             = SharedSecrets.getJavaLangReflectModuleAccess()
                            .defineUnnamedModule(this);
         if (ParallelLoaders.isRegistered(this.getClass())) {

@@ -354,10 +366,31 @@
             assertionLock = this;
         }
     }
 
     /**
+     * Creates a new class loader of the specified name and using the
+     * specified parent class loader for delegation.
+     *
+     * @param  name   class loader name; or {@code null} if not named
+     * @param  parent the parent class loader
+     *
+     * @throws IllegalArgumentException if the given name is empty.
+     *
+     * @throws SecurityException
+     *         If a security manager exists and its
+     *         {@link SecurityManager#checkCreateClassLoader()}
+     *         method doesn't allow creation of a new class loader.
+     *
+     * @since  9
+     */
+    protected ClassLoader(String name, ClassLoader parent) {
+        this(checkCreateClassLoader(name), name, parent);
+    }
+
+
+    /**
      * Creates a new class loader using the specified parent class loader for
      * delegation.
      *
      * <p> If there is a security manager, its {@link
      * SecurityManager#checkCreateClassLoader()

@@ -373,13 +406,14 @@
      *          of a new class loader.
      *
      * @since  1.2
      */
     protected ClassLoader(ClassLoader parent) {
-        this(checkCreateClassLoader(), parent);
+        this(checkCreateClassLoader(), null, parent);
     }
 
+
     /**
      * Creates a new class loader using the <tt>ClassLoader</tt> returned by
      * the method {@link #getSystemClassLoader()
      * <tt>getSystemClassLoader()</tt>} as the parent class loader.
      *

@@ -392,11 +426,35 @@
      *          If a security manager exists and its
      *          <tt>checkCreateClassLoader</tt> method doesn't allow creation
      *          of a new class loader.
      */
     protected ClassLoader() {
-        this(checkCreateClassLoader(), getSystemClassLoader());
+        this(checkCreateClassLoader(), null, getSystemClassLoader());
+    }
+
+
+    /**
+     * Returns the name of this class loader or {@code null} if
+     * this class loader is not named.
+     *
+     * @apiNote This method is non-final for compatibility.  If this
+     * method is overridden, this method must return the same name
+     * as specified when this class loader was instantiated.
+     *
+     * @return name of this class loader; or {@code null} if
+     * this class loader is not named.
+     *
+     * @since 9
+     */
+    public String getName() {
+        return name;
+    }
+
+    // package-private used by StackTraceElement to avoid
+    // calling the overrideable getName method
+    final String name() {
+        return name;
     }
 
     // -- Class --
 
     /**

@@ -1626,10 +1684,13 @@
     /**
      * Returns the platform class loader for delegation.  All
      * <a href="#builtinLoaders">platform classes</a> are visible to
      * the platform class loader.
      *
+     * @implNote The name of the builtin platform class loader is
+     * {@code "platform"}.
+     *
      * @return  The platform {@code ClassLoader}.
      *
      * @throws  SecurityException
      *          If a security manager is present, and the caller's class loader is
      *          not {@code null}, and the caller's class loader is not the same

@@ -1679,11 +1740,12 @@
      * @implNote The system property to override the system class loader is not
      * examined until the VM is almost fully initialized. Code that executes
      * this method during startup should take care not to cache the return
      * value until the system is fully initialized.
      *
-     * <p> The class path used by the built-in system class loader is determined
+     * <p> The name of the built-in system class loader is {@code "app"}.
+     * The class path used by the built-in system class loader is determined
      * by the system property "{@code java.class.path}" during early
      * initialization of the VM. If the system property is not defined,
      * or its value is an empty string, then there is no class path
      * when the initial module is a module on the application module path,
      * i.e. <em>a named module</em>. If the initial module is not on