ArrayList源码分析

(1) JDK1.8底层是Object类型数组

transient Object[] elementData; // non-private to simplify nested class access

    
private int size;

(2) ArrayList list = new ArrayList();调用空构造器：

public ArrayList() {
    this.elementData = DEFAULTCAPACITY_EMPTY_ELEMENTDATA;
}
private static final Object[] EMPTY_ELEMENTDATA = {};

 (3) add方法