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java.lang.Object
Object is the root of the class hierarchy. Every class has Object as a superclass. All objects, including arrays, implement the methods of this class. 
Object() 
clone() equals(Object) finalize() getClass() hashCode() notify() notifyAll() toString() wait() wait(long) wait(long, int) 
Object
public Object()
getClass
public final native Class getClass()
Class that represents the runtime class of the object. hashCode
public native int hashCode()
java.util.Hashtable. The general contract of hashCode is:
hashCode method must consistently return the same integer. This integer need not remain consistent from one execution of an application to another execution of the same application. equals method, then calling the hashCode method on each of the two objects must produce the same integer result. equals
public boolean equals(Object obj)
The equals method implements an equivalence relation:
x, x.equals(x) should return true. x and y, x.equals(y) should return true if and only if y.equals(x) returns true. x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true. x and y, multiple invocations of x.equals(y) consistently return true or consistently return false. x, x.equals(null) should return false. The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any reference values x and y, this method returns true if and only if x and y refer to the same object (x==y has the value true).
true if this object is the same as the obj argument; false otherwise. clone
protected native Object clone() throws CloneNotSupportedException
The clone method of class Object will only clone an object whose class indicates that it is willing for its instances to be cloned. A class indicates that its instances can be cloned by declaring that it implements the Cloneable interface.
Cloneable interface. Subclasses that override the clone method can also throw this exception to indicate that an instance cannot be cloned. toString
public String toString()
toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommendedthat all subclasses override this method. The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object.
notify
public final native void notify()
wait methods. This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:
synchronized statement that synchronizes on the object. Class, by executing a synchronized static method of that class. Only one thread at a time can own an object's monitor.
notifyAll
public final native void notifyAll()
wait methods. This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
wait
public final native void wait(long timeout) throws InterruptedException
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:
notify method or the notifyAll method. timeout argument in milliseconds, has elapsed. The thread then waits until it can re-obtain ownership of the monitor and resumes execution.
This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
wait
public final void wait(long timeout,
int nanos) throws InterruptedException
This method is similar to the wait method of one argument, but it allows finer control over the amount of time to wait for a notification before giving up.
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:
notify method or the notifyAll method. timeout milliseconds plus nanos nanoseconds arguments, has elapsed. The thread then waits until it can re-obtain ownership of the monitor and resumes execution
This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
wait
public final void wait() throws InterruptedException
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until another thread notifies threads waiting on this object's monitor to wake up either through a call to the notify method or the notifyAll method. The thread then waits until it can re-obtain ownership of the monitor and resumes execution.
This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.
finalize
protected void finalize() throws Throwable
finalize method to dispose of system resources or to perform other cleanup. Any exception thrown by the finalize method causes the finalization of this object to be halted, but is otherwise ignored.
The finalize method in Object does nothing.
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