#vulnerable code 
                                private static MemoryLayoutSpecification getEffectiveMemoryLayoutSpecification() {

        final String dataModel = System.getProperty("sun.arch.data.model");
        if ("32".equals(dataModel)) {
            // Running with 32-bit data model
            return new MemoryLayoutSpecification() {
                public int getArrayHeaderSize() {
                    return 12;
                }

                public int getObjectHeaderSize() {
                    return 8;
                }

                public int getObjectPadding() {
                    return 8;
                }

                public int getReferenceSize() {
                    return 4;
                }

                public int getSuperclassFieldPadding() {
                    return 4;
                }
            };
        }

        final String strVmVersion = System.getProperty("java.vm.version");
        final int vmVersion = Integer.parseInt(strVmVersion.substring(0, strVmVersion.indexOf('.')));
        final int alignment = getAlignment();
        if (vmVersion >= 17) {

            long maxMemory = 0;
            for (MemoryPoolMXBean mp : ManagementFactory.getMemoryPoolMXBeans()) {
                maxMemory += mp.getUsage().getMax();
            }

            if (maxMemory < 30L * 1024 * 1024 * 1024) {
                // HotSpot 17.0 and above use compressed OOPs below 30GB of RAM
                // total for all memory pools (yes, including code cache).
                return new MemoryLayoutSpecification() {

                    public int getArrayHeaderSize() {
                        return 16;
                    }

                    public int getObjectHeaderSize() {
                        return 12;
                    }

                    public int getObjectPadding() {
                        return alignment;
                    }

                    public int getReferenceSize() {
                        return 4;
                    }

                    public int getSuperclassFieldPadding() {
                        return 4;
                    }
                };
            }
        }

        /* Worst case we over count. */

        // In other cases, it's a 64-bit uncompressed OOPs object model
        return new MemoryLayoutSpecification() {

            public int getArrayHeaderSize() {
                return 24;
            }

            public int getObjectHeaderSize() {
                return 16;
            }

            public int getObjectPadding() {
                return alignment;
            }

            public int getReferenceSize() {
                return 8;
            }

            public int getSuperclassFieldPadding() {
                return 8;
            }
        };
    } 
                            #location 30 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private static MemoryLayoutSpecification getEffectiveMemoryLayoutSpecification() {

        final String dataModel = System.getProperty("sun.arch.data.model");
        if ("32".equals(dataModel)) {
            // Running with 32-bit data model
            return new MemoryLayoutSpecification() {
                public int getArrayHeaderSize() {
                    return 12;
                }

                public int getObjectHeaderSize() {
                    return 8;
                }

                public int getObjectPadding() {
                    return 8;
                }

                public int getReferenceSize() {
                    return 4;
                }

                public int getSuperclassFieldPadding() {
                    return 4;
                }
            };
        }

        boolean modernJvm = true;

        final String strSpecVersion = System.getProperty("java.specification.version");
        final boolean hasDot = strSpecVersion.indexOf('.') != -1;
        if (hasDot) {
            if ("1".equals(strSpecVersion.substring(0, strSpecVersion.indexOf('.')))) {
                // Java 1.6, 1.7, 1.8
                final String strVmVersion = System.getProperty("java.vm.version");
                final int vmVersion = Integer.parseInt(strVmVersion.substring(0, strVmVersion.indexOf('.')));
                modernJvm = vmVersion >= 17;
            }
        }

        final int alignment = getAlignment();
        if (modernJvm) {

            long maxMemory = 0;
            for (MemoryPoolMXBean mp : ManagementFactory.getMemoryPoolMXBeans()) {
                maxMemory += mp.getUsage().getMax();
            }

            if (maxMemory < 30L * 1024 * 1024 * 1024) {
                // HotSpot 17.0 and above use compressed OOPs below 30GB of RAM
                // total for all memory pools (yes, including code cache).
                return new MemoryLayoutSpecification() {

                    public int getArrayHeaderSize() {
                        return 16;
                    }

                    public int getObjectHeaderSize() {
                        return 12;
                    }

                    public int getObjectPadding() {
                        return alignment;
                    }

                    public int getReferenceSize() {
                        return 4;
                    }

                    public int getSuperclassFieldPadding() {
                        return 4;
                    }
                };
            }
        }

        /* Worst case we over count. */

        // In other cases, it's a 64-bit uncompressed OOPs object model
        return new MemoryLayoutSpecification() {

            public int getArrayHeaderSize() {
                return 24;
            }

            public int getObjectHeaderSize() {
                return 16;
            }

            public int getObjectPadding() {
                return alignment;
            }

            public int getReferenceSize() {
                return 8;
            }

            public int getSuperclassFieldPadding() {
                return 8;
            }
        };
    }