blocks|key|1419690|text|您可以在创建元素时将元素的数量设置为所需的任何内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419691|xClass[]+mysclass+=+new+xClass[n];|code-block|syntax|javascript|1419692|然后，您可以在循环中初始化元素。我猜这就是你所需要的。|1419693|如果在创建数组后需要向数组中添加或删除元素，则必须使用ArrayList。|offset|length|style|CODE|1419694|entityMap^0|0|0|0|R|9|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|T|8|@$K|U|L|V|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

You set the number of elements to anything you want at the time you create it:

<pre><code>xClass[] mysclass = new xClass[n];
</code></pre>

Then you can initialize the elements in a loop. I am guessing that this is what you need.

If you need to add or remove elements to the array after you create it, then you would have to use an <code>ArrayList</code>.

blocks|key|1204643|text|不，数组一旦创建，就不能改变其大小。您要么必须分配比您认为需要的更大的空间，要么接受必须重新分配空间的开销。当它发生时，你将不得不分配一个新的，并将数据从旧的复制到新的：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1204644|int[]+oldItems+=+new+int[10];
for+(int+i+=+0;+i+<+10;+i%2B%2B)+{
++++oldItems[i]+=+i+%2B+10;
}
int[]+newItems+=+new+int[20];
System.arraycopy(oldItems,+0,+newItems,+0,+10);
oldItems+=+newItems;|code-block|syntax|javascript|1204645|如果您发现自己处于这种情况，我强烈建议您改用Java+Collections。特别是，ArrayList本质上包装了一个数组，并负责根据需要增加数组的逻辑：|offset|length|style|CODE|1204646|List<XClass>+myclass+=+new+ArrayList<XClass>();
myclass.add(new+XClass());
myclass.add(new+XClass());|1204647|通常，出于以下几个原因，ArrayList是一个比数组更可取的解决方案。首先，数组是可变的。如果你有一个这样的类：|1204648|class+Myclass+{
++++private+int[]+items;

++++public+int[]+getItems()+{
++++++++return+items;
++++}
}|1204649|你已经制造了一个问题，因为调用者可以改变你的私有数据成员，这导致了各种防御性的复制。将此版本与列表版本进行比较：|1204650|class+Myclass+{
++++private+List<Integer>+items;

++++public+List<Integer>+getItems()+{
++++++++return+Collections.unmodifiableList(items);
++++}
}|1204651|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/6/docs/api/java/util/ArrayList.html^0|0|0|17|9|17|9|0|0|0|C|9|0|0|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|16|8|@$I|17|J|18|K|L]]|9|@$I|19|J|1A|1|1B]]|A|$]]|$1|M|3|N|5|D|7|1C|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1D|8|@$I|1E|J|1F|K|L]]|9|@]|A|$]]|$1|Q|3|R|5|D|7|1G|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|1H|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|1I|8|@]|9|@]|A|$E|F]]|$1|W|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]]|X|$Y|$5|Z|10|11|A|$12|13]]]]

No you can't change the size of an array once created. You either have to allocate it bigger than you think you'll need or accept the overhead of having to reallocate it needs to grow in size. When it does you'll have to allocate a new one and copy the data from the old to the new:

<pre><code>int[] oldItems = new int[10];
for (int i = 0; i &lt; 10; i++) {
 oldItems[i] = i + 10;
}
int[] newItems = new int[20];
System.arraycopy(oldItems, 0, newItems, 0, 10);
oldItems = newItems;
</code></pre>

If you find yourself in this situation, I'd highly recommend using the Java Collections instead. In particular <a href="http://docs.oracle.com/javase/6/docs/api/java/util/ArrayList.html" rel="noreferrer"><code>ArrayList</code></a> essentially wraps an array and takes care of the logic for growing the array as required:

<pre><code>List&lt;XClass&gt; myclass = new ArrayList&lt;XClass&gt;();
myclass.add(new XClass());
myclass.add(new XClass());
</code></pre>

Generally an <code>ArrayList</code> is a preferable solution to an array anyway for several reasons. For one thing, arrays are mutable. If you have a class that does this:

<pre><code>class Myclass {
 private int[] items;

 public int[] getItems() {
 return items;
 }
}
</code></pre>

you've created a problem as a caller can change your private data member, which leads to all sorts of defensive copying. Compare this to the List version:

<pre><code>class Myclass {
 private List&lt;Integer&gt; items;

 public List&lt;Integer&gt; getItems() {
 return Collections.unmodifiableList(items);
 }
}
</code></pre>

blocks|key|1419793|text|其中，将myclass[]数组声明为：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419794|xClass+myclass[]+=+new+xClass[10]|code-block|syntax|javascript|1419795|，只需将所需的XClass元素数量作为参数传入即可。在这一点上，你知道你需要多少？通过将数组声明为具有10个元素，您并没有声明10个xClass对象，而只是创建了一个包含10个XClass类型元素的数组。|1419796|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Where you declare the myclass[] array as :

<pre><code>xClass myclass[] = new xClass[10]
</code></pre>

, simply pass in as an argument the number of XClass elements you'll need. At that point do you know how many you will need? By declaring the array as having 10 elements, you are not declaring 10 XClass objects, you're simply creating an array with 10 elements of type xClass.

blocks|key|1419818|text|是的，包装它并使用Collections框架。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419819|List+l+=+new+ArrayList();
l.add(new+xClass());
//+do+stuff
l.add(new+xClass());|code-block|syntax|javascript|1419820|然后在必要时使用List.toArray()，或者只迭代所述列表。|1419821|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Yes, wrap it and use the Collections framework.

<pre><code>List l = new ArrayList();
l.add(new xClass());
// do stuff
l.add(new xClass());
</code></pre>

Then use List.toArray() when necessary, or just iterate over said List.

blocks|key|1204751|text|在java数组中，长度是固定的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1204752|如果需要，您可以使用列表来保存这些值并调用toArray方法，请参阅以下示例：|offset|length|style|CODE|1204753|import+java.util.List;
import+java.util.ArrayList;
import+java.util.Random;

public+class+A++{

++++public+static+void+main(+String+[]+args+)+{
++++++++//+dynamically+hold+the+instances
++++++++List<xClass>+list+=+new+ArrayList<xClass>();

++++++++//+fill+it+with+a+random+number+between+0+and+100
++++++++int+elements+=+new+Random().nextInt(100);++
++++++++for(+int+i+=+0+;+i+<+elements+;+i%2B%2B+)+{
++++++++++++list.add(+new+xClass()+);
++++++++}

++++++++//+convert+it+to+array
++++++++xClass+[]+array+=+list.toArray(+new+xClass[+list.size()+]+);


++++++++System.out.println(+"size+of+array+=+"+%2B+array.length+);
++++}
}
class+xClass+{}|code-block|syntax|javascript|1204754|entityMap^0|0|L|7|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|S|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

In java array length is fixed.

You can use a List to hold the values and invoke the <code>toArray</code> method if needed
See the following sample:

<pre><code>import java.util.List;
import java.util.ArrayList;
import java.util.Random;

public class A {

 public static void main( String [] args ) {
 // dynamically hold the instances
 List&lt;xClass&gt; list = new ArrayList&lt;xClass&gt;();

 // fill it with a random number between 0 and 100
 int elements = new Random().nextInt(100); 
 for( int i = 0 ; i &lt; elements ; i++ ) {
 list.add( new xClass() );
 }

 // convert it to array
 xClass [] array = list.toArray( new xClass[ list.size() ] );


 System.out.println( "size of array = " + array.length );
 }
}
class xClass {}
</code></pre>

blocks|key|1419879|text|Arrays.copyOf()方法有许多选项来解决数组长度动态增加的问题。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1419880|Java+API|1419881|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/7/docs/api/java/util/Arrays.html#copyOf(T[],%2520int)^0|0|F|0|0|8|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|S|8|@]|D|@$9|T|A|U|1|V]]|E|$]]|$1|H|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]]]

<code>Arrays.copyOf()</code> method has many options to fix the problem with Array length increasing dynamically.

<a href="http://docs.oracle.com/javase/7/docs/api/java/util/Arrays.html#copyOf(T[],%20int)" rel="nofollow noreferrer">Java API</a>

blocks|key|1419886|text|您可以使用ArrayList：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419887|import+java.util.ArrayList;
import+java.util.Iterator;|code-block|syntax|javascript|1419888|..。|1419889|ArrayList<String>+arr+=+new+ArrayList<String>();
arr.add("neo");
arr.add("morpheus");
arr.add("trinity");
Iterator<String>+foreach+=+arr.iterator();
while+(foreach.hasNext())+System.out.println(foreach.next());|1419890|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You can use ArrayList:

<pre><code>import java.util.ArrayList;
import java.util.Iterator;
</code></pre>

...

<pre><code>ArrayList&lt;String&gt; arr = new ArrayList&lt;String&gt;();
arr.add("neo");
arr.add("morpheus");
arr.add("trinity");
Iterator&lt;String&gt; foreach = arr.iterator();
while (foreach.hasNext()) System.out.println(foreach.next());
</code></pre>

blocks|key|1419910|text|这是一个很好的做法，首先获取需要存储的数量，然后初始化数组。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419911|例如，您可以询问用户需要存储多少数据，然后对其进行初始化，或者查询需要存储多少数据的组件或参数。如果你想要一个动态数组，你可以使用ArrayList()，并使用al.add();函数不断加法，然后你可以把它转换成一个固定的数组。|offset|length|style|CODE|1419912|//Initialize+ArrayList+and+cast+string+so+ArrayList+accepts+strings+(or+anything
ArrayList<string>+al+=+new+ArrayList();+
//add+a+certain+amount+of+data
for(int+i=0;i<x;i%2B%2B)
{
++al.add("data+"%2Bi);+
}

//get+size+of+data+inside
int+size+=+al.size();+
//initialize+String+array+with+the+size+you+have
String+strArray[]+=+new+String[size];+
//insert+data+from+ArrayList+to+String+array
for(int+i=0;i<size;i%2B%2B)
{
++strArray[i]+=+al.get(i);
}|code-block|syntax|javascript|1419913|这样做是多余的，但只是为了向您展示一下想法，ArrayList可以保存不同于其他原始数据类型的对象，并且非常容易操作，从中间删除任何东西也很容易，完全使用List和Stack的dynamic.same|1419914|entityMap^0|0|1T|B|28|9|0|0|M|9|25|4|2A|5|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@$D|S|E|T|F|G]|$D|U|E|V|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|W|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|X|8|@$D|Y|E|Z|F|G]|$D|10|E|11|F|G]|$D|12|E|13|F|G]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|P|$]]

It is a good practice get the amount you need to store first then initialize the array.

for example, you would ask the user how many data he need to store and then initialize it, or query the component or argument of how many you need to store.
if you want a dynamic array you could use <code>ArrayList()</code> and use <code>al.add();</code> function to keep adding, then you can transfer it to a fixed array.

<pre><code>//Initialize ArrayList and cast string so ArrayList accepts strings (or anything
ArrayList&lt;string&gt; al = new ArrayList(); 
//add a certain amount of data
for(int i=0;i&lt;x;i++)
{
 al.add("data "+i); 
}

//get size of data inside
int size = al.size(); 
//initialize String array with the size you have
String strArray[] = new String[size]; 
//insert data from ArrayList to String array
for(int i=0;i&lt;size;i++)
{
 strArray[i] = al.get(i);
}
</code></pre>

doing so is redundant but just to show you the idea, <code>ArrayList</code> can hold objects unlike other primitive data types and are very easy to manipulate, removing anything from the middle is easy as well, completely dynamic.same with <code>List</code> and <code>Stack</code>

blocks|key|1419932|text|Java数组的大小是固定的，您不能像在C%2B%2B中那样创建动态数组。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419933|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Java Array sizes are fixed , You cannot make dynamic Arrays as that of in C++.

blocks|key|1419939|text|我不知道您是否可以在运行时更改大小，但您可以在运行时分配大小。尝试使用以下代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1419940|class+MyClass+{
++++void+myFunction+()+{
++++++++Scanner+s+=+new+Scanner+(System.in);
++++++++int+myArray+[];
++++++++int+x;

++++++++System.out.print+("Enter+the+size+of+the+array:+");
++++++++x+=+s.nextInt();

++++++++myArray+=+new+int[x];
++++}
}|code-block|syntax|javascript|1419941|这会将您的数组大小指定为运行时输入到x的数组大小。|1419942|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I don't know if you can change the size at runtime but you can allocate the size at runtime. Try using this code:

<pre><code>class MyClass {
 void myFunction () {
 Scanner s = new Scanner (System.in);
 int myArray [];
 int x;

 System.out.print ("Enter the size of the array: ");
 x = s.nextInt();

 myArray = new int[x];
 }
}
</code></pre>

this assigns your array size to be the one entered at run time into x.

blocks|key|1204884|text|这里有一个不使用ArrayList的方法。用户指定大小，您可以添加用于递归的do-while循环。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1204885|import+java.util.Scanner;
++++public+class+Dynamic+{
++++++++public+static+Scanner+value;
++++++++public+static+void+main(String[]args){
++++++++++++value=new+Scanner(System.in);
++++++++++++System.out.println("Enter+the+number+of+tests+to+calculate+average\n");
++++++++++++int+limit=value.nextInt();
++++++++++++int+index=0;
++++++++++++int+[]+marks=new+int[limit];
++++++++++++float+sum,ave;
++++++++++++sum=0;++++++
++++++++++++while(index<limit)
++++++++++++{
++++++++++++++++int+test=index%2B1;
++++++++++++++++System.out.println("Enter+the+marks+on+test+"+%2Btest);
++++++++++++++++marks[index]=value.nextInt();
++++++++++++++++sum%2B=marks[index];
++++++++++++++++index%2B%2B;
++++++++++++}
++++++++++++ave=sum/limit;
++++++++++++System.out.println("The+average+is:+"+%2B+ave);
++++++++}
++++}|code-block|syntax|javascript|1204886|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here's a method that doesn't use ArrayList. The user specifies the size and you can add a do-while loop for recursion.

<pre><code>import java.util.Scanner;
 public class Dynamic {
 public static Scanner value;
 public static void main(String[]args){
 value=new Scanner(System.in);
 System.out.println("Enter the number of tests to calculate average\n");
 int limit=value.nextInt();
 int index=0;
 int [] marks=new int[limit];
 float sum,ave;
 sum=0; 
 while(index&lt;limit)
 {
 int test=index+1;
 System.out.println("Enter the marks on test " +test);
 marks[index]=value.nextInt();
 sum+=marks[index];
 index++;
 }
 ave=sum/limit;
 System.out.println("The average is: " + ave);
 }
 }
</code></pre>

blocks|key|1204906|text|是的，我们可以这样做。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1204907|import+java.util.Scanner;

public+class+Collection_Basic+{

++++private+static+Scanner+sc;

++++public+static+void+main(String[]+args)+{

++++++++Object[]+obj=new+Object[4];
++++++++sc+=+new+Scanner(System.in);


++++++++//Storing+element
++++++++System.out.println("enter+your+element");
++++++++for(int+i=0;i<4;i%2B%2B){
++++++++++++obj[i]=sc.nextInt();
++++++++}

++++++++/*
+++++++++*+here,+size+reaches+with+its+maximum+capacity+so+u+can+not+store+more+element,
+++++++++*+
+++++++++*+for+storing+more+element+we+have+to+create+new+array+Object+with+required+size
+++++++++*/

++++++++Object[]+tempObj=new+Object[10];

++++++++//copying+old+array+to+new+Array

++++++++int+oldArraySize=obj.length;
++++++++int+i=0;
++++++++for(;i<oldArraySize;i%2B%2B){

++++++++++++tempObj[i]=obj[i];
++++++++}

++++++++/*
+++++++++*+storing+new+element+to+the+end+of+new+Array+objebt
+++++++++*/
++++++++tempObj[i]=90;

++++++++//assigning+new+array+Object+refeence+to+the+old+one

++++++++obj=tempObj;

++++++++for(int+j=0;j<obj.length;j%2B%2B){
++++++++++++System.out.println("obj["%2Bj%2B"]+-"%2Bobj[j]);
++++++++}
++++}


}|code-block|syntax|javascript|1204908|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Yes, we can do this way.

<pre><code>import java.util.Scanner;

public class Collection_Basic {

 private static Scanner sc;

 public static void main(String[] args) {

 Object[] obj=new Object[4];
 sc = new Scanner(System.in);


 //Storing element
 System.out.println("enter your element");
 for(int i=0;i&lt;4;i++){
 obj[i]=sc.nextInt();
 }

 /*
 * here, size reaches with its maximum capacity so u can not store more element,
 * 
 * for storing more element we have to create new array Object with required size
 */

 Object[] tempObj=new Object[10];

 //copying old array to new Array

 int oldArraySize=obj.length;
 int i=0;
 for(;i&lt;oldArraySize;i++){

 tempObj[i]=obj[i];
 }

 /*
 * storing new element to the end of new Array objebt
 */
 tempObj[i]=90;

 //assigning new array Object refeence to the old one

 obj=tempObj;

 for(int j=0;j&lt;obj.length;j++){
 System.out.println("obj["+j+"] -"+obj[j]);
 }
 }


}
</code></pre>

blocks|key|1420049|text|因为当我需要原始类型的数组时，ArrayList会占用很多内存，所以我更喜欢使用IntStream.builder()来创建整数数组(您也可以使用LongStream和DoubleStream构建器)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1420050|示例：|1420051|Builder+builder+=+IntStream.builder();
int+arraySize+=+new+Random().nextInt();
for(int+i+=+0;+i<arraySize;+i%2B%2B+)+{
++++builder.add(i);
}
int[]+array+=+builder.build().toArray();|code-block|syntax|javascript|1420052|注意:从Java+8开始可用。|1420053|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Since ArrayList takes to much memory when I need array of primitive types, I prefer using IntStream.builder() for creating int array (You can also use LongStream and DoubleStream builders).

Example:

<pre><code>Builder builder = IntStream.builder();
int arraySize = new Random().nextInt();
for(int i = 0; i&lt;arraySize; i++ ) {
 builder.add(i);
}
int[] array = builder.build().toArray();
</code></pre>

Note: available since Java 8.

blocks|key|1204980|text|你可以做一些事情|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1204981|private++static+Person+[]++addPersons(Person[]+persons,+Person+personToAdd)+{
++++int+currentLenght+=+persons.length;

++++Person+[]+personsArrayNew+=+Arrays.copyOf(persons,+currentLenght+%2B1);
++++personsArrayNew[currentLenght]++=+personToAdd;

++++return+personsArrayNew;

}|code-block|syntax|javascript|1204982|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can do some thing 

<pre><code>private static Person [] addPersons(Person[] persons, Person personToAdd) {
 int currentLenght = persons.length;

 Person [] personsArrayNew = Arrays.copyOf(persons, currentLenght +1);
 personsArrayNew[currentLenght] = personToAdd;

 return personsArrayNew;

}
</code></pre>

I have a class - xClass, that I want to load into an array of xClass so I the declaration:

<pre><code>xClass mysclass[] = new xClass[10];
myclass[0] = new xClass();
myclass[9] = new xClass();
</code></pre>

However, I don't know if I will need 10. I may need 8 or 12 or any other number for that matter. I won't know until runtime. 
Can I change the number of elements in an array on the fly? 
If so, how?

Java dynamic array sizes?

Java

我有一个类- xClass，我想把它加载到一个xClass数组中，这样我就可以声明：xClass mysclass[] = new xClass[10];myclass[0] = new xClass();myclass[9] = new xClass();然而，我不知道我是否需要10。我可能需要8或12或任何其他数字...

问Java动态数组大小？
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