JVM对象内存布局工具箱

pom依赖

 <dependency>
            <groupId>org.openjdk.jol</groupId>
            <artifactId>jol-core</artifactId>
            <version>0.9</version>
        </dependency>

查看object对象内存布局

 public static void main(String[] args) {
        Object o = new Object();
        System.out.println(ClassLayout.parseInstance(o).toPrintable());
    }