Java 源码分析-Object 类

Object 介绍

Java Object 类是所有类的父类，也就是说 Java 的所有类都继承了 Object，子类可以使用 Object 的所有方法。

Object 源码

package java.lang;

public class Object {
    private static native void registerNatives();
    static {
        registerNatives();
    }

    public final native Class<?> getClass();

    public native int hashCode();

    public boolean equals(Object obj) {
        return (this == obj);
    }

    protected native Object clone() throws CloneNotSupportedException;

    public String toString() {
        return getClass().getName() + "@" + Integer.toHexString(hashCode());
    }

    public final native void notify();

    public final native void notifyAll();

    public final native void wait(long timeout) throws InterruptedException;

    public final void wait(long timeout, int nanos) throws InterruptedException {
        if (timeout < 0) {
            throw new IllegalArgumentException("timeout value is negative");
        }
        if (nanos < 0 || nanos > 999999) {
            throw new IllegalArgumentException(
                    "nanosecond timeout value out of range");
        }
        if (nanos > 0) {
            timeout++;
        }
        wait(timeout);
    }

    public final void wait() throws InterruptedException {
        wait(0);
    }

    /**
     * 垃圾回收的时候执行此方法。
     */
    protected void finalize() throws Throwable {}
}

使用示例

public class Test {
    public static void main(String args[]) {
        Object obj = new Object();
        System.out.println(obj.toString());
    }
}

控制台输出：
java.lang.Object@6d1e7682