ConstantPool::allocate记录

allocate记录"/>

ConstantPool::allocate记录

常量池的开辟方法

ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));

ConstantPool* ConstantPool::allocate(ClassLoaderData* loader_data, int length, TRAPS) {Array<u1>* tags = MetadataFactory::new_writeable_array<u1>(loader_data, length, 0, CHECK_NULL);int size = ConstantPool::size(length);return new (loader_data, size, false, MetaspaceObj::ConstantPoolType, THREAD) ConstantPool(tags);
}

此处的new为运算符重载查看父类new的重载方法

void* MetaspaceObj::operator new(size_t size, ClassLoaderData* loader_data,size_t word_size, bool read_only,MetaspaceObj::Type type, TRAPS) throw() {// Klass has it's own operator newreturn Metaspace::allocate(loader_data, word_size, read_only,type, CHECK_NULL);
}

刚开始看的时候，反复对了参数，看这个重载方法怎么多个size参数，查看资料才明白这个new的关键字的函数原型为operator new(size_t size);这个size为sizeof(类)计算出来类的大小，这里c++默认给你做了处理，至此对new运算符更新了认识，其他初学者也会犯这种低级的错误，原因在于没有仔细了解过new的运算符重载。