voidTypeArrayKlass::copy_array(arrayOop s,int src_pos,arrayOop d,int dst_pos,int length,TRAPS){assert(s->is_typeArray(),"must be type array");// Check destinationif(!d->is_typeArray()||element_type()!=TypeArrayKlass::cast(d->klass())->element_type()){THROW(vmSymbols::java_la...
When we want to copy an object in Java, there are two possibilities that we need to consider,a shallow copy and a deep copy. For the shallow copy approach, we only copy field values, therefore the copy might be dependant on the original object. In the deep copy approach, we make sure...
/*** 复制数组,数组扩容,无论数组是扩容还是变小,原数组是不会改变的*/publicstaticvoidmakeArrayCopy() {//复制数组,这里用到的是java.util.Arrays类中的copyOf()方法int[] array = {2,4,6};int[] newArray =Arrays.copyOf(array, array.length);//判断两个数组是否相等,用到的是Arrays类中的equals...
}//Check zero copyif(length ==0)return;//This is an attempt to make the copy_array fast.intl2es =log2_element_size();intihs = array_header_in_bytes() /wordSize;char* src = (char*) ((oop*)s + ihs) + ((size_t)src_pos <<l2es);char* dst = (char*) ((oop*)d + ihs)...
宏展开将数组备份、对象分配和加锁解锁等节点展开成一个优化版本的Fast/Slow形式,使得System.arraycopy、Arrays.copyOf等调用可以高效进行。 最终理想图变形是机器无关优化的最后一步,位于 Compile::final_graph_reshaping()。在这一步,编译器会尝试发现无限循环,由于在代码生成阶段很多算法不能很好地处理无限循环,所以...
// Make shallow object copy const int size = obj->size(); oop new_obj = NULL; if (obj->is_array()) { const int length = ((arrayOop)obj())->length(); new_obj = CollectedHeap::array_allocate(klass, size, length, CHECK_NULL); ...
实际上,我们只是把copyClass1所指向的在堆(Heap)中的地址赋给了copyClass2. 因此导致了改变了copyClass2.X的值后copyClass1.X的值也被改变。 1. 拷贝原型 为了在Heap中重新创建一片新的地址,我们有如下方案可以选择: 1. 直接用Setter和Getter复制
Deep copy with the clone() method Now we know that theclone()method won’t work for a deep copy if we have a simple override. Let’s see how we can make it work. First, we implementCloneablein theCategoryclass: publicclassCategoryimplementsCloneable{// Omitted attributes, constructor, gett...
Array Array ArrayBlockingQueue ArrayDeque ArrayIndexOutOfBoundsException ArrayList Arrays ArrayStoreException ArrayType ArrayType AssertionError AsyncBoxView AsyncHandler AsynchronousCloseException AtomicBoolean AtomicInteger AtomicIntegerArray AtomicIntegerFieldUpdater AtomicLong AtomicLongArray ...
can make a deep copy of an object by using the Cloneable() interface and overriding the clone() method. Copy constructors are an easier and more flexible way of performing a deep copy. We can also use Serialization but we need to remember that its computation is expensive than other ...