The findclass and findmethod functions in debug.cpp are for examining classes/methods in a debugger (such as gdb)

https://github.com/openjdk/jdk/blob/6ec36d348b1eaeedb993a905e42650242fac0918/src/hotspot/share/utilities/debug.cpp#L583-L603

This REF improves these functions by:

- Sorting the names of classes and methods
- Allow "." to be used in class names. So both findclass("java.lang.Object") and findclass("java/lang/Object") would work
- Print the contents of InstanceKlass and Java mirrors.

Example:

(gdb) p findclass("*.ArrayList", 0x20)

"Executing findclass"
flags (bitmask):
   0x01 - print names of methods
   0x02 - print bytecodes
   0x04 - print the address of bytecodes
   0x08 - print info for invokedynamic
   0x10 - print info for invokehandle
   0x20 - print details of the C++ and Java objects that represent classes
   0x40 - print details of the C++ objects that represent methods

[ 0] 0x000000005527ddb8 class: java/util/ArrayList mirror: 0x00000007ff854410 loader data: 0x00007ffff010cf30 of 'bootstrap'
InstanceKlass: java.util.ArrayList {0x000000005527ddb8}
 - instance size: 3
 - klass size: 205
 - access: public synchronized
 - flags: rewritten has_nonstatic_fields has_nonstatic_concrete_methods defined_by_boot_loader has_localvariable_table has_miranda_methods
 - state: fully_initialized
 - name: 'java/util/ArrayList'
 - super: 'java/util/AbstractList'
 - sub:
 - arrays: null
 - methods: Array<T>(0x000000005591e538)
 - method ordering: Array<T>(0x000000005577a0d8)
 - default_methods: Array<T>(0x000000005591f438)
 - default vtable indices: Array<T>(0x000000005577a1f0)
 - local interfaces: Array<T>(0x000000005591f468)
 - trans. interfaces: Array<T>(0x000000005591f490)
 - secondary supers: Array<T>(0x0000000055918860)
 - hash_slot: 26
 - secondary bitmap: 0x4000000100220203
 - constants: constant pool [516] {0x000000005591b918} for 'java/util/ArrayList' cache=0x0000000055282018
 - class loader data: loader data: 0x00007ffff010cf30 of 'bootstrap'
 - source file: 'ArrayList.java'
 - generic signature: '<E:Ljava/lang/Object;>Ljava/util/AbstractList<TE;>;Ljava/util/List<TE;>;Ljava/util/RandomAccess;Ljava/lang/Cloneable;Ljava/io/Serializable;'
 - inner classes: Array<T>(0x0000000055779f68)
 - nest members: Array<T>(0x000000005577a238)
 - permitted subclasses: Array<T>(0x00000000557590b0)
 - java mirror: a 'java/lang/Class'{0x00000007ff854410} = 'java/util/ArrayList'
 - vtable length 55 (start addr: 0x000000005527df98)
 - itable length 89 (start addr: 0x000000005527e150)
 - ---- static fields (3 words):
 - private static final 'serialVersionUID' 'J' @128
 - private static final 'DEFAULT_CAPACITY' 'I' @136
 - private static final 'EMPTY_ELEMENTDATA' '[Ljava/lang/Object;' @120
 - private static final 'DEFAULTCAPACITY_EMPTY_ELEMENTDATA' '[Ljava/lang/Object;' @124
 - ---- non-static fields (3 words):
 - protected transient 'modCount' 'I' @12
 - private 'size' 'I' @16
 - transient 'elementData' '[Ljava/lang/Object;' @20
 - non-static oop maps (1 entries): 20-20

Java mirror oop for java/util/ArrayList: java.lang.Class
{0x00000007ff854410} - klass: 'java/lang/Class' - flags:

 - ---- fields (total size 18 words):
 - private volatile transient 'classRedefinedCount' 'I' @12 0 (0x00000000)
 - injected 'klass' 'J' @16 1428676024 (0x000000005527ddb8)
 - injected 'array_klass' 'J' @24 0 (0x0000000000000000)
 - injected 'oop_size' 'I' @32 18 (0x00000012)
 - injected 'static_oop_field_count' 'I' @36 2 (0x00000002)
 - private final transient 'modifiers' 'C' @40 1 (0x0001)
 - private final transient 'classFileAccessFlags' 'C' @42 ! 33 (0x0021)
 - private final transient 'primitive' 'Z' @44 false (0x00)
 - private volatile transient 'cachedConstructor' 'Ljava/lang/reflect/Constructor;' @48 null (0x00000000)
 - private transient 'name' 'Ljava/lang/String;' @52 null (0x00000000)
 - private transient 'module' 'Ljava/lang/Module;' @56 a 'java/lang/Module'{0x00000007ff8205a0} (0xfff040b4)
 - private final 'classLoader' 'Ljava/lang/ClassLoader;' @60 null (0x00000000)
 - private transient 'classData' 'Ljava/lang/Object;' @64 null (0x00000000)
 - private transient 'signers' '[Ljava/lang/Object;' @68 null (0x00000000)
 - private transient 'packageName' 'Ljava/lang/String;' @72 null (0x00000000)
 - private final transient 'componentType' 'Ljava/lang/Class;' @76 null (0x00000000)
 - private final transient 'protectionDomain' 'Ljava/security/ProtectionDomain;' @80 null (0x00000000)
 - private volatile transient 'reflectionData' 'Ljava/lang/ref/SoftReference;' @84 null (0x00000000)
 - private volatile transient 'genericInfo' 'Lsun/reflect/generics/repository/ClassRepository;' @88 null (0x00000000)
 - private volatile transient 'enumConstants' '[Ljava/lang/Object;' @92 null (0x00000000)
 - private volatile transient 'enumConstantDirectory' 'Ljava/util/Map;' @96 null (0x00000000)
 - private volatile transient 'annotationData' 'Ljava/lang/Class$AnnotationData;' @100 null (0x00000000)
 - private volatile transient 'annotationType' 'Lsun/reflect/annotation/AnnotationType;' @104 null (0x00000000)
 - transient 'classValueMap' 'Ljava/lang/ClassValue$ClassValueMap;' @108 null (0x00000000)
 - injected 'source_file' 'Ljava/lang/Object;' @112 null (0x00000000)
 - injected '<init_lock>' 'Ljava/lang/Object;' @116 null (0x00000000)
 - signature: Ljava/util/ArrayList;
 - ---- static fields (2):
 - private static final 'serialVersionUID' 'J' @128 8683452581122892189 (0x7881d21d99c7619d)
 - private static final 'DEFAULT_CAPACITY' 'I' @136 10 (0x0000000a)
 - private static final 'EMPTY_ELEMENTDATA' '[Ljava/lang/Object;' @120 a 'java/lang/Object'[0] {0x000000043800f188} (0x87001e31)
 - private static final 'DEFAULTCAPACITY_EMPTY_ELEMENTDATA' '[Ljava/lang/Object;' @124 a 'java/lang/Object'[0] {0x000000043800f198} (0x87001e33)