Merge

agent/src/os/bsd/ps_core.c

@@ -199,10 +199,10 @@ static map_info* core_lookup(struct ps_prochandle *ph, uintptr_t addr)
 //---------------------------------------------------------------
 // Part of the class sharing workaround:
 //
-// With class sharing, pages are mapped from classes[_g].jsa file.
+// With class sharing, pages are mapped from classes.jsa file.
 // The read-only class sharing pages are mapped as MAP_SHARED,
 // PROT_READ pages. These pages are not dumped into core dump.
-// With this workaround, these pages are read from classes[_g].jsa.
+// With this workaround, these pages are read from classes.jsa.
 
 // FIXME: !HACK ALERT!
 // The format of sharing achive file header is needed to read shared heap
@@ -298,14 +298,12 @@ static bool init_classsharing_workaround(struct ps_prochandle* ph) {
   lib_info* lib = ph->libs;
   while (lib != NULL) {
     // we are iterating over shared objects from the core dump. look for
-    // libjvm[_g].so.
+    // libjvm.so.
     const char *jvm_name = 0;
 #ifdef __APPLE__
-    if ((jvm_name = strstr(lib->name, "/libjvm.dylib")) != 0 ||
-        (jvm_name = strstr(lib->name, "/libjvm_g.dylib")) != 0)
+    if ((jvm_name = strstr(lib->name, "/libjvm.dylib")) != 0)
 #else
-    if ((jvm_name = strstr(lib->name, "/libjvm.so")) != 0 ||
-        (jvm_name = strstr(lib->name, "/libjvm_g.so")) != 0)
+    if ((jvm_name = strstr(lib->name, "/libjvm.so")) != 0)
 #endif // __APPLE__
     {
       char classes_jsa[PATH_MAX];
@@ -389,7 +387,7 @@ static bool init_classsharing_workaround(struct ps_prochandle* ph) {
       }
 
       ph->core->classes_jsa_fd = fd;
-      // add read-only maps from classes[_g].jsa to the list of maps
+      // add read-only maps from classes.jsa to the list of maps
       for (m = 0; m < NUM_SHARED_MAPS; m++) {
         if (header._space[m]._read_only) {
           base = (uintptr_t) header._space[m]._base;

agent/src/os/linux/ps_core.c

@@ -195,10 +195,10 @@ static map_info* core_lookup(struct ps_prochandle *ph, uintptr_t addr)
 //---------------------------------------------------------------
 // Part of the class sharing workaround:
 //
-// With class sharing, pages are mapped from classes[_g].jsa file.
+// With class sharing, pages are mapped from classes.jsa file.
 // The read-only class sharing pages are mapped as MAP_SHARED,
 // PROT_READ pages. These pages are not dumped into core dump.
-// With this workaround, these pages are read from classes[_g].jsa.
+// With this workaround, these pages are read from classes.jsa.
 
 // FIXME: !HACK ALERT!
 // The format of sharing achive file header is needed to read shared heap
@@ -284,10 +284,9 @@ static bool init_classsharing_workaround(struct ps_prochandle* ph) {
    lib_info* lib = ph->libs;
    while (lib != NULL) {
       // we are iterating over shared objects from the core dump. look for
-      // libjvm[_g].so.
+      // libjvm.so.
       const char *jvm_name = 0;
-      if ((jvm_name = strstr(lib->name, "/libjvm.so")) != 0 ||
-          (jvm_name = strstr(lib->name, "/libjvm_g.so")) != 0) {
+      if ((jvm_name = strstr(lib->name, "/libjvm.so")) != 0) {
          char classes_jsa[PATH_MAX];
          struct FileMapHeader header;
          size_t n = 0;
@@ -371,7 +370,7 @@ static bool init_classsharing_workaround(struct ps_prochandle* ph) {
          }
 
          ph->core->classes_jsa_fd = fd;
-         // add read-only maps from classes[_g].jsa to the list of maps
+         // add read-only maps from classes.jsa to the list of maps
          for (m = 0; m < NUM_SHARED_MAPS; m++) {
             if (header._space[m]._read_only) {
                base = (uintptr_t) header._space[m]._base;

agent/src/os/solaris/proc/saproc.cpp

@@ -589,8 +589,7 @@ init_classsharing_workaround(void *cd, const prmap_t* pmap, const char* obj_name
   JNIEnv*   env = dbg->env;
   jobject this_obj = dbg->this_obj;
   const char* jvm_name = 0;
-  if ((jvm_name = strstr(obj_name, "libjvm.so")) != NULL ||
-      (jvm_name = strstr(obj_name, "libjvm_g.so")) != NULL) {
+  if ((jvm_name = strstr(obj_name, "libjvm.so")) != NULL) {
     jvm_name = obj_name;
   } else {
     return 0;
@@ -598,7 +597,7 @@ init_classsharing_workaround(void *cd, const prmap_t* pmap, const char* obj_name
 
   struct ps_prochandle* ph = (struct ps_prochandle*) env->GetLongField(this_obj, p_ps_prochandle_ID);
 
-  // initialize classes[_g].jsa file descriptor field.
+  // initialize classes.jsa file descriptor field.
   dbg->env->SetIntField(this_obj, classes_jsa_fd_ID, -1);
 
   // check whether class sharing is on by reading variable "UseSharedSpaces"
@@ -641,7 +640,7 @@ init_classsharing_workaround(void *cd, const prmap_t* pmap, const char* obj_name
 
   print_debug("looking for %s\n", classes_jsa);
 
-  // open the classes[_g].jsa
+  // open the classes.jsa
   int fd = libsaproc_open(classes_jsa, O_RDONLY);
   if (fd < 0) {
     char errMsg[ERR_MSG_SIZE];
@@ -651,7 +650,7 @@ init_classsharing_workaround(void *cd, const prmap_t* pmap, const char* obj_name
     print_debug("opened shared archive file %s\n", classes_jsa);
   }
 
-  // parse classes[_g].jsa
+  // parse classes.jsa
   struct FileMapHeader* pheader = (struct FileMapHeader*) malloc(sizeof(struct FileMapHeader));
   if (pheader == NULL) {
     close(fd);
@@ -798,8 +797,8 @@ static void attach_internal(JNIEnv* env, jobject this_obj, jstring cmdLine, jboo
   if (! isProcess) {
     /*
      * With class sharing, shared perm. gen heap is allocated in with MAP_SHARED|PROT_READ.
-     * These pages are mapped from the file "classes[_g].jsa". MAP_SHARED pages are not dumped
-     * in Solaris core.To read shared heap pages, we have to read classes[_g].jsa file.
+     * These pages are mapped from the file "classes.jsa". MAP_SHARED pages are not dumped
+     * in Solaris core.To read shared heap pages, we have to read classes.jsa file.
      */
     Pobject_iter(ph, init_classsharing_workaround, &dbg);
     exception = env->ExceptionOccurred();

agent/src/share/classes/sun/jvm/hotspot/HotSpotAgent.java

@@ -24,20 +24,29 @@
 
 package sun.jvm.hotspot;
 
-import java.io.PrintStream;
-import java.net.*;
-import java.rmi.*;
-import sun.jvm.hotspot.debugger.*;
-import sun.jvm.hotspot.debugger.bsd.*;
-import sun.jvm.hotspot.debugger.proc.*;
-import sun.jvm.hotspot.debugger.remote.*;
-import sun.jvm.hotspot.debugger.windbg.*;
-import sun.jvm.hotspot.debugger.linux.*;
-import sun.jvm.hotspot.memory.*;
-import sun.jvm.hotspot.oops.*;
-import sun.jvm.hotspot.runtime.*;
-import sun.jvm.hotspot.types.*;
-import sun.jvm.hotspot.utilities.*;
+import java.rmi.RemoteException;
+
+import sun.jvm.hotspot.debugger.Debugger;
+import sun.jvm.hotspot.debugger.DebuggerException;
+import sun.jvm.hotspot.debugger.JVMDebugger;
+import sun.jvm.hotspot.debugger.MachineDescription;
+import sun.jvm.hotspot.debugger.MachineDescriptionAMD64;
+import sun.jvm.hotspot.debugger.MachineDescriptionIA64;
+import sun.jvm.hotspot.debugger.MachineDescriptionIntelX86;
+import sun.jvm.hotspot.debugger.MachineDescriptionSPARC32Bit;
+import sun.jvm.hotspot.debugger.MachineDescriptionSPARC64Bit;
+import sun.jvm.hotspot.debugger.NoSuchSymbolException;
+import sun.jvm.hotspot.debugger.bsd.BsdDebuggerLocal;
+import sun.jvm.hotspot.debugger.linux.LinuxDebuggerLocal;
+import sun.jvm.hotspot.debugger.proc.ProcDebuggerLocal;
+import sun.jvm.hotspot.debugger.remote.RemoteDebugger;
+import sun.jvm.hotspot.debugger.remote.RemoteDebuggerClient;
+import sun.jvm.hotspot.debugger.remote.RemoteDebuggerServer;
+import sun.jvm.hotspot.debugger.windbg.WindbgDebuggerLocal;
+import sun.jvm.hotspot.runtime.VM;
+import sun.jvm.hotspot.types.TypeDataBase;
+import sun.jvm.hotspot.utilities.PlatformInfo;
+import sun.jvm.hotspot.utilities.UnsupportedPlatformException;
 
 /** <P> This class wraps much of the basic functionality and is the
  * highest-level factory for VM data structures. It makes it simple
@@ -475,7 +484,7 @@ public class HotSpotAgent {
     }
 
     private void setupJVMLibNamesSolaris() {
-        jvmLibNames = new String[] { "libjvm.so", "libjvm_g.so", "gamma_g" };
+        jvmLibNames = new String[] { "libjvm.so" };
     }
 
     //
@@ -507,7 +516,7 @@ public class HotSpotAgent {
     }
 
     private void setupJVMLibNamesWin32() {
-        jvmLibNames = new String[] { "jvm.dll", "jvm_g.dll" };
+        jvmLibNames = new String[] { "jvm.dll" };
     }
 
     //
@@ -547,7 +556,7 @@ public class HotSpotAgent {
     }
 
     private void setupJVMLibNamesLinux() {
-        jvmLibNames = new String[] { "libjvm.so", "libjvm_g.so" };
+        jvmLibNames = new String[] { "libjvm.so" };
     }
 
     //
@@ -572,7 +581,7 @@ public class HotSpotAgent {
     }
 
     private void setupJVMLibNamesBsd() {
-        jvmLibNames = new String[] { "libjvm.so", "libjvm_g.so" };
+        jvmLibNames = new String[] { "libjvm.so" };
     }
 
     //
@@ -595,7 +604,7 @@ public class HotSpotAgent {
     }
 
     private void setupJVMLibNamesDarwin() {
-        jvmLibNames = new String[] { "libjvm.dylib", "libjvm_g.dylib" };
+        jvmLibNames = new String[] { "libjvm.dylib" };
     }
 
     /** Convenience routine which should be called by per-platform

agent/src/share/classes/sun/jvm/hotspot/LinuxVtblAccess.java

@@ -24,9 +24,9 @@
 
 package sun.jvm.hotspot;
 
-import sun.jvm.hotspot.debugger.*;
-import sun.jvm.hotspot.types.*;
-import sun.jvm.hotspot.types.basic.*;
+import sun.jvm.hotspot.debugger.SymbolLookup;
+import sun.jvm.hotspot.types.Type;
+import sun.jvm.hotspot.types.basic.BasicVtblAccess;
 
 public class LinuxVtblAccess extends BasicVtblAccess {
   private String vt;
@@ -35,8 +35,7 @@ public class LinuxVtblAccess extends BasicVtblAccess {
                          String[] dllNames) {
     super(symbolLookup, dllNames);
 
-    if (symbolLookup.lookup("libjvm.so", "__vt_10JavaThread") != null ||
-        symbolLookup.lookup("libjvm_g.so", "__vt_10JavaThread") != null) {
+    if (symbolLookup.lookup("libjvm.so", "__vt_10JavaThread") != null) {
        // old C++ ABI
        vt = "__vt_";
     } else {

agent/src/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java

@@ -24,17 +24,28 @@
 
 package sun.jvm.hotspot.debugger.bsd;
 
-import java.io.*;
-import java.net.*;
-import java.util.*;
-import sun.jvm.hotspot.debugger.*;
-import sun.jvm.hotspot.debugger.x86.*;
-import sun.jvm.hotspot.debugger.cdbg.*;
-import sun.jvm.hotspot.utilities.*;
-import sun.jvm.hotspot.runtime.VM;
-import sun.jvm.hotspot.runtime.Threads;
+import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+
+import sun.jvm.hotspot.debugger.Address;
+import sun.jvm.hotspot.debugger.DebuggerBase;
+import sun.jvm.hotspot.debugger.DebuggerException;
+import sun.jvm.hotspot.debugger.DebuggerUtilities;
+import sun.jvm.hotspot.debugger.MachineDescription;
+import sun.jvm.hotspot.debugger.NotInHeapException;
+import sun.jvm.hotspot.debugger.OopHandle;
+import sun.jvm.hotspot.debugger.ReadResult;
+import sun.jvm.hotspot.debugger.ThreadProxy;
+import sun.jvm.hotspot.debugger.UnalignedAddressException;
+import sun.jvm.hotspot.debugger.UnmappedAddressException;
+import sun.jvm.hotspot.debugger.cdbg.CDebugger;
+import sun.jvm.hotspot.debugger.cdbg.ClosestSymbol;
+import sun.jvm.hotspot.debugger.cdbg.LoadObject;
 import sun.jvm.hotspot.runtime.JavaThread;
-import java.lang.reflect.*;
+import sun.jvm.hotspot.runtime.Threads;
+import sun.jvm.hotspot.runtime.VM;
+import sun.jvm.hotspot.utilities.PlatformInfo;
 
 /** <P> An implementation of the JVMDebugger interface. The basic debug
     facilities are implemented through ptrace interface in the JNI code
@@ -246,10 +257,8 @@ public class BsdDebuggerLocal extends DebuggerBase implements BsdDebugger {
     /* called from attach methods */
     private void findABIVersion() throws DebuggerException {
         String libjvmName = isDarwin ? "libjvm.dylib" : "libjvm.so";
-        String libjvm_gName = isDarwin? "libjvm_g.dylib" : "libjvm_g.so";
         String javaThreadVt = isDarwin ? "_vt_10JavaThread" : "__vt_10JavaThread";
-        if (lookupByName0(libjvmName, javaThreadVt) != 0 ||
-            lookupByName0(libjvm_gName, javaThreadVt) != 0) {
+        if (lookupByName0(libjvmName, javaThreadVt) != 0) {
             // old C++ ABI
             useGCC32ABI = false;
         } else {

agent/src/share/classes/sun/jvm/hotspot/debugger/linux/LinuxDebuggerLocal.java

@@ -24,14 +24,25 @@
 
 package sun.jvm.hotspot.debugger.linux;
 
-import java.io.*;
-import java.net.*;
-import java.util.*;
-import sun.jvm.hotspot.debugger.*;
-import sun.jvm.hotspot.debugger.x86.*;
-import sun.jvm.hotspot.debugger.cdbg.*;
-import sun.jvm.hotspot.utilities.*;
-import java.lang.reflect.*;
+import java.io.File;
+import java.util.ArrayList;
+import java.util.List;
+
+import sun.jvm.hotspot.debugger.Address;
+import sun.jvm.hotspot.debugger.DebuggerBase;
+import sun.jvm.hotspot.debugger.DebuggerException;
+import sun.jvm.hotspot.debugger.DebuggerUtilities;
+import sun.jvm.hotspot.debugger.MachineDescription;
+import sun.jvm.hotspot.debugger.NotInHeapException;
+import sun.jvm.hotspot.debugger.OopHandle;
+import sun.jvm.hotspot.debugger.ReadResult;
+import sun.jvm.hotspot.debugger.ThreadProxy;
+import sun.jvm.hotspot.debugger.UnalignedAddressException;
+import sun.jvm.hotspot.debugger.UnmappedAddressException;
+import sun.jvm.hotspot.debugger.cdbg.CDebugger;
+import sun.jvm.hotspot.debugger.cdbg.ClosestSymbol;
+import sun.jvm.hotspot.debugger.cdbg.LoadObject;
+import sun.jvm.hotspot.utilities.PlatformInfo;
 
 /** <P> An implementation of the JVMDebugger interface. The basic debug
     facilities are implemented through ptrace interface in the JNI code
@@ -238,8 +249,7 @@ public class LinuxDebuggerLocal extends DebuggerBase implements LinuxDebugger {
 
     /* called from attach methods */
     private void findABIVersion() throws DebuggerException {
-        if (lookupByName0("libjvm.so", "__vt_10JavaThread") != 0 ||
-            lookupByName0("libjvm_g.so", "__vt_10JavaThread") != 0) {
+        if (lookupByName0("libjvm.so", "__vt_10JavaThread") != 0) {
             // old C++ ABI
             useGCC32ABI = false;
         } else {

src/share/vm/prims/jvmtiClassFileReconstituter.cpp

@@ -350,13 +350,13 @@ void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_n
 //        u2 bootstrap_arguments[num_bootstrap_arguments];
 //    } bootstrap_methods[num_bootstrap_methods];
 //  }
-void JvmtiClassFileReconstituter::write_boostrapmethod_attribute() {
+void JvmtiClassFileReconstituter::write_bootstrapmethod_attribute() {
   Array<u2>* operands = cpool()->operands();
   write_attribute_name_index("BootstrapMethods");
   int num_bootstrap_methods = ConstantPool::operand_array_length(operands);
 
   // calculate length of attribute
-  int length = sizeof(u2); // num_boostrap_methods
+  int length = sizeof(u2); // num_bootstrap_methods
   for (int n = 0; n < num_bootstrap_methods; n++) {
     u2 num_bootstrap_arguments = cpool()->operand_argument_count_at(n);
     length += sizeof(u2); // bootstrap_method_ref
@@ -657,7 +657,7 @@ void JvmtiClassFileReconstituter::write_class_attributes() {
     write_annotations_attribute("RuntimeVisibleAnnotations", anno);
   }
   if (cpool()->operands() != NULL) {
-    write_boostrapmethod_attribute();
+    write_bootstrapmethod_attribute();
   }
 }
 

src/share/vm/prims/jvmtiClassFileReconstituter.hpp

@@ -127,7 +127,7 @@ class JvmtiClassFileReconstituter : public JvmtiConstantPoolReconstituter {
   void write_signature_attribute(u2 generic_signaure_index);
   void write_attribute_name_index(const char* name);
   void write_annotations_attribute(const char* attr_name, AnnotationArray* annos);
-  void write_boostrapmethod_attribute();
+  void write_bootstrapmethod_attribute();
 
   address writeable_address(size_t size);
   void write_u1(u1 x);

test/runtime/ClassUnload/KeepAliveClass.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * @test KeepAliveClass
+ * @summary This test case uses a java.lang.Class instance to keep a class alive.
+ * @library /testlibrary /testlibrary/whitebox /runtime/testlibrary
+ * @library classes
+ * @build KeepAliveClass test.Empty
+ * @build ClassUnloadCommon
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI KeepAliveClass
+ */
+
+import java.lang.ref.SoftReference;
+import sun.hotspot.WhiteBox;
+
+/**
+ * Test that verifies that classes are not unloaded when specific types of references are kept to them.
+ */
+public class KeepAliveClass {
+  private static final String className = "test.Empty";
+  private static final WhiteBox wb = WhiteBox.getWhiteBox();
+  public static Object escape = null;
+
+  public static void main(String... args) throws Exception {
+    ClassLoader cl = ClassUnloadCommon.newClassLoader();
+    Class<?> c = cl.loadClass(className);
+    Object o = c.newInstance();
+    o = null; cl = null;
+    escape = c;
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClass (1) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClass (2) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+    c = null;
+    escape = null;
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClass (3) alive: " + isAlive);
+        ClassUnloadCommon.failIf(isAlive, "should be unloaded");
+    }
+
+  }
+}

test/runtime/ClassUnload/KeepAliveClassLoader.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * @test KeepAliveClassLoader
+ * @summary This test case uses a java.lang.ClassLoader instance to keep a class alive.
+ * @library /testlibrary /testlibrary/whitebox /runtime/testlibrary
+ * @library classes
+ * @build KeepAliveClassLoader test.Empty
+ * @build ClassUnloadCommon
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI KeepAliveClassLoader
+ */
+
+import sun.hotspot.WhiteBox;
+
+/**
+ * Test that verifies that classes are not unloaded when specific types of references are kept to them.
+ */
+public class KeepAliveClassLoader {
+  private static final String className = "test.Empty";
+  private static final WhiteBox wb = WhiteBox.getWhiteBox();
+  public static Object escape = null;
+
+
+  public static void main(String... args) throws Exception {
+    ClassLoader cl = ClassUnloadCommon.newClassLoader();
+    Class<?> c = cl.loadClass(className);
+    Object o = c.newInstance();
+    o = null; c = null;
+    escape = cl;
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClassLoader (1) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClassLoader (2) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+    cl = null;
+    escape = null;
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testClassLoader (3) alive: " + isAlive);
+        ClassUnloadCommon.failIf(isAlive, "should be unloaded");
+    }
+
+  }
+}

test/runtime/ClassUnload/KeepAliveObject.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * @test KeepAliveObject
+ * @summary This test case uses a class instance to keep the class alive.
+ * @library /testlibrary /testlibrary/whitebox /runtime/testlibrary
+ * @library classes
+ * @build KeepAliveObject test.Empty
+ * @build ClassUnloadCommon
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI KeepAliveObject
+ */
+
+import sun.hotspot.WhiteBox;
+
+/**
+ * Test that verifies that classes are not unloaded when specific types of references are kept to them.
+ */
+public class KeepAliveObject {
+  private static final String className = "test.Empty";
+  private static final WhiteBox wb = WhiteBox.getWhiteBox();
+  public static Object escape = null;
+
+  public static void main(String... args) throws Exception {
+    ClassLoader cl = ClassUnloadCommon.newClassLoader();
+    Class<?> c = cl.loadClass(className);
+    Object o = c.newInstance();
+    cl = null; c = null;
+    escape = o;
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testObject (1) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testObject (2) alive: " + isAlive);
+
+        ClassUnloadCommon.failIf(!isAlive, "should be alive");
+    }
+    o = null;
+    escape = null;
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testObject (3) alive: " + isAlive);
+        ClassUnloadCommon.failIf(isAlive, "should be unloaded");
+    }
+
+  }
+}

test/runtime/ClassUnload/KeepAliveSoftReference.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * @test KeepAliveSoftReference
+ * @summary This test case uses a java.lang.ref.SoftReference referencing a class instance to keep a class alive.
+ * @library /testlibrary /testlibrary/whitebox /runtime/testlibrary
+ * @library classes
+ * @build KeepAliveSoftReference test.Empty
+ * @build ClassUnloadCommon
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI KeepAliveSoftReference
+ */
+
+import java.lang.ref.SoftReference;
+import sun.hotspot.WhiteBox;
+
+/**
+ * Test that verifies that classes are not unloaded when specific types of references are kept to them.
+ */
+public class KeepAliveSoftReference {
+  private static final String className = "test.Empty";
+  private static final WhiteBox wb = WhiteBox.getWhiteBox();
+
+  public static void main(String... args) throws Exception {
+    ClassLoader cl = ClassUnloadCommon.newClassLoader();
+    Class<?> c = cl.loadClass(className);
+    Object o = c.newInstance();
+    SoftReference<Object> sr = new SoftReference(o);
+    o = null; c = null; cl = null;
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testSoftReference (1) alive: " + isAlive);
+        boolean cleared = (sr.get() == null);
+        boolean shouldBeAlive = !cleared;
+        ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
+    }
+
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testSoftReference (2) alive: " + isAlive);
+        boolean cleared = (sr.get() == null);
+        boolean shouldBeAlive = !cleared;
+        ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
+    }
+    sr.clear();
+    ClassUnloadCommon.triggerUnloading();
+
+    {
+        boolean isAlive = wb.isClassAlive(className);
+        System.out.println("testSoftReference (3) alive: " + isAlive);
+        boolean cleared = (sr.get() == null);
+        boolean shouldBeAlive = !cleared;
+        ClassUnloadCommon.failIf(isAlive != shouldBeAlive, "" + isAlive + " != " + shouldBeAlive);
+    }
+  }
+}

test/runtime/ClassUnload/UnloadTest.java

+/*
+ * Copyright (c) 2013, 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.
+ */
+
+/*
+ * @test UnloadTest
+ * @library /runtime/testlibrary /testlibrary /testlibrary/whitebox
+ * @library classes
+ * @build ClassUnloadCommon test.Empty
+ * @build UnloadTest
+ * @run main ClassFileInstaller sun.hotspot.WhiteBox
+ * @run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI UnloadTest
+ */
+import sun.hotspot.WhiteBox;
+
+/**
+ * Test that verifies that classes are unloaded when they are no longer reachable.
+ *
+ * The test creates a class loader, uses the loader to load a class and creates an instance
+ * of that class. The it nulls out all the references to the instance, class and class loader
+ * and tries to trigger class unloading. Then it verifies that the class is no longer
+ * loaded by the VM.
+ */
+public class UnloadTest {
+    private static String className = "test.Empty";
+
+    public static void main(String... args) throws Exception {
+       run();
+    }
+
+    private static void run() throws Exception {
+        final WhiteBox wb = WhiteBox.getWhiteBox();
+
+        ClassUnloadCommon.failIf(wb.isClassAlive(className), "is not expected to be alive yet");
+
+        ClassLoader cl = ClassUnloadCommon.newClassLoader();
+        Class<?> c = cl.loadClass(className);
+        Object o = c.newInstance();
+
+        ClassUnloadCommon.failIf(!wb.isClassAlive(className), "should be live here");
+
+        cl = null; c = null; o = null;
+        ClassUnloadCommon.triggerUnloading();
+        ClassUnloadCommon.failIf(wb.isClassAlive(className), "should have been unloaded");
+    }
+}
+

test/runtime/ClassUnload/classes/test/Empty.java

+package test;
+
+public class Empty {
+public String toString() { return "nothing"; }
+}

test/runtime/testlibrary/ClassUnloadCommon.java

+/*
+ * Copyright (c) 2013, 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 java.io.File;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+
+public class ClassUnloadCommon {
+    public static class TestFailure extends RuntimeException {
+        TestFailure(String msg) {
+            super(msg);
+        }
+    }
+
+    public static void failIf(boolean value, String msg) {
+        if (value) throw new TestFailure("Test failed: " + msg);
+    }
+
+    private static volatile Object dummy = null;
+    private static void allocateMemory(int kilobytes) {
+        ArrayList<byte[]> l = new ArrayList<>();
+        dummy = l;
+        for (int i = kilobytes; i > 0; i -= 1) {
+            l.add(new byte[1024]);
+        }
+        l = null;
+        dummy = null;
+    }
+
+    public static void triggerUnloading() {
+        allocateMemory(16 * 1024); // yg size is 8m with cms, force young collection
+        System.gc();
+    }
+
+    public static ClassLoader newClassLoader() {
+        try {
+            return new URLClassLoader(new URL[] {
+                Paths.get(System.getProperty("test.classes",".") + File.separatorChar + "classes").toUri().toURL(),
+            }, null);
+        } catch (MalformedURLException e){
+            throw new RuntimeException("Unexpected URL conversion failure", e);
+        }
+    }
+
+}