[Java] Runtime Data Areas of JVM ref: http://qiita.com/SHUAI/items/9cd4b78f874f5a11c48c

file0.java

public void add(java.lang.String);
  Code:
   Stack=2, Locals=2, Args_size=2
   0:   aload_0
   1:   getfield        #15; //Field admin:Lcom/nhn/user/UserAdmin;
   4:   aload_1
   5:   invokevirtual   #23; //Method com/nhn/user/UserAdmin.addUser:(Ljava/lang/String;)Lcom/nhn/user/User;
   8:   pop
   9:   return  LineNumberTable:
   line 14: 0
   line 15: 9  LocalVariableTable:
   Start  Length  Slot  Name   Signature
   0      10      0    this       Lcom/nhn/service/UserService;
   0      10      1    userName       Ljava/lang/String; // … Omitted - Other method information …
}

file1.java

public class SimpleClass {

    public int simpleField = 100;

}

file2.java

public SimpleClass();
  Signature: ()V
  flags: ACC_PUBLIC
  Code:
    Stack=2, Locals=1, Args_size=1
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: aload_0
       5: bipush        100
       7: putfield      #2                  // Field simpleField:I
      10: return

file3.java

   #1 = Methodref          #4.#16         //  java/lang/Object."<init>":()V
   #2 = Fieldref           #3.#17         //  SimpleClass.simpleField:I
   #3 = Class              #13            //  SimpleClass
   #4 = Class              #19            //  java/lang/Object
   #5 = Utf8               simpleField
   #6 = Utf8               I
   #7 = Utf8               <init>
   #8 = Utf8               ()V
   #9 = Utf8               Code
  #10 = Utf8               LineNumberTable
  #11 = Utf8               LocalVariableTable
  #12 = Utf8               this
  #13 = Utf8               SimpleClass
  #14 = Utf8               SourceFile
  #15 = Utf8               SimpleClass.java
  #16 = NameAndType        #7:#8          //  "<init>":()V
  #17 = NameAndType        #5:#6          //  simpleField:I
  #18 = Utf8               LSimpleClass;
  #19 = Utf8               java/lang/Object

file4.java

public class TestClass {
    public static void main(String[] args)  {
        Object foo = null;
        Object bar = null;
    }
}

file5.java

public static void main(java.lang.String[]);
  Code:
   Stack=1, Locals=3, Args_size=1
   0:   aconst_null
   1:   astore_1
   2:   aconst_null
   3:   astore_2
   4:   return

LineNumberTable: 
line 5: 0
line 6: 2
line 7: 4

LocalVariableTable: 
Start  Length  Slot  Name   Signature
0      5      0    args       [Ljava/lang/String;
2      3      1    foo       Ljava/lang/Object;
4      1      2    bar       Ljava/lang/Object;