blocks|key|1510798|text|一种选择是传入Bar.class+(或您感兴趣的任何类型-以任何方式指定适当的Class<T>引用)，并将该值作为字段保留：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1510799|public+class+Test+{
++++public+static+void+main(String[]+args)+throws+IllegalAccessException,
++++++++++++InstantiationException+{
++++++++Generic<Bar>+x+=+new+Generic<>(Bar.class);
++++++++Bar+y+=+x.buildOne();
++++}
}

public+class+Generic<T>+{
++++private+Class<T>+clazz;

++++public+Generic(Class<T>+clazz)+{
++++++++this.clazz+=+clazz;
++++}

++++public+T+buildOne()+throws+InstantiationException,+IllegalAccessException+{
++++++++return+clazz.newInstance();
++++}
}

public+class+Bar+{
++++public+Bar()+{
++++++++System.out.println("Constructing");
++++}
}|code-block|syntax|javascript|1510800|另一种选择是使用“工厂”接口，然后将工厂传递给泛型类的构造函数。这更加灵活，而且您不需要担心反射异常。|1510801|entityMap^0|7|9|13|8|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

One option is to pass in <code>Bar.class</code> (or whatever type you're interested in - any way of specifying the appropriate <code>Class&lt;T&gt;</code> reference) and keep that value as a field:

<pre><code>public class Test {
 public static void main(String[] args) throws IllegalAccessException,
 InstantiationException {
 Generic&lt;Bar&gt; x = new Generic&lt;&gt;(Bar.class);
 Bar y = x.buildOne();
 }
}

public class Generic&lt;T&gt; {
 private Class&lt;T&gt; clazz;

 public Generic(Class&lt;T&gt; clazz) {
 this.clazz = clazz;
 }

 public T buildOne() throws InstantiationException, IllegalAccessException {
 return clazz.newInstance();
 }
}

public class Bar {
 public Bar() {
 System.out.println("Constructing");
 }
}
</code></pre>

Another option is to have a "factory" interface, and you pass a factory to the constructor of the generic class. That's more flexible, and you don't need to worry about the reflection exceptions.

blocks|key|1296245|text|Java语言中的泛型通常比C#中的更强大。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1296246|如果你想构造一个对象，但又不想硬连接一个构造函数/静态方法，那就使用抽象工厂。您应该能够在任何基本设计模式书籍、OOP入门或互联网上找到有关抽象工厂模式的详细信息和教程。除了提到Java的闭包语法很糟糕之外，这里不值得重复代码。|1296247|IIRC，C#有一个特殊情况，用于指定具有无参数构造函数的泛型类型。根据定义，这种不规则性的前提是客户端代码希望使用这种特定的构造形式，并鼓励易变性。|1296248|使用反射来解决这个问题是错误的。Java中的泛型是一种编译时的静态类型特性。试图在运行时使用它们是出了问题的明显迹象。反射会导致冗长的代码、运行时失败、未经检查的依赖项和安全漏洞。(Class.forName特别邪恶。)|offset|length|style|CODE|1296249|entityMap^0|0|0|0|2J|D|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|P|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|Q|8|@$H|R|I|S|J|K]]|9|@]|A|$]]|$1|L|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|M|$]]

Generics in Java are generally more powerful than in C#.

If you want to construct an object but without hardwiring a constructor/static method, use an abstract factory. You should be able to find detailed information and tutorials on the Abstract Factory Pattern in any basic design patterns book, introduction to OOP or all over the interwebs. It's not worth duplicating code here, other than to mention that Java's closure syntax sucks.

IIRC, C# has a special case for specifying a generic type has a no-args constructor. This irregularity, by definition, presupposes that client code wants to use this particular form of construction and encourages mutability.

Using reflection for this is just wrongheaded. Generics in Java are a compile-time, static-typing feature. Attempts to use them at runtime are a clear indication of something going wrong. Reflection causes verbose code, runtime failures, unchecked dependencies and security vulnerabilities. (<code>Class.forName</code> is particularly evil.)

blocks|key|1510922|text|这里有一种不需要显式使用构造函数参数的人为方法。你需要扩展一个参数化的抽象类。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1510923|public+class+Test+{+++
++++public+static+void+main(String+[]+args)+throws+Exception+{
++++++++Generic+g+=+new+Generic();
++++++++g.initParameter();
++++}
}

import+java.lang.reflect.ParameterizedType;
public+abstract+class+GenericAbstract<T+extends+Foo>+{
++++protected+T+parameter;

++++@SuppressWarnings("unchecked")
++++void+initParameter()+throws+Exception,+ClassNotFoundException,+
++++++++InstantiationException+{
++++++++//+Get+the+class+name+of+this+instance's+type.
++++++++ParameterizedType+pt
++++++++++++=+(ParameterizedType)+getClass().getGenericSuperclass();
++++++++//+You+may+need+this+split+or+not,+use+logging+to+check
++++++++String+parameterClassName
++++++++++++=+pt.getActualTypeArguments()[0].toString().split("\\s")[1];
++++++++//+Instantiate+the+Parameter+and+initialize+it.
++++++++parameter+=+(T)+Class.forName(parameterClassName).newInstance();
++++}
}

public+class+Generic+extends+GenericAbstract<Foo>+{
}

public+class+Foo+{
++++public+Foo()+{
++++++++System.out.println("Foo+constructor...");
++++}
}|code-block|syntax|javascript|1510924|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 rather contrived way to do it without explicitly using an constructor argument. You need to extend a parameterized abstract class.

<pre><code>public class Test { 
 public static void main(String [] args) throws Exception {
 Generic g = new Generic();
 g.initParameter();
 }
}

import java.lang.reflect.ParameterizedType;
public abstract class GenericAbstract&lt;T extends Foo&gt; {
 protected T parameter;

 @SuppressWarnings("unchecked")
 void initParameter() throws Exception, ClassNotFoundException, 
 InstantiationException {
 // Get the class name of this instance's type.
 ParameterizedType pt
 = (ParameterizedType) getClass().getGenericSuperclass();
 // You may need this split or not, use logging to check
 String parameterClassName
 = pt.getActualTypeArguments()[0].toString().split("\\s")[1];
 // Instantiate the Parameter and initialize it.
 parameter = (T) Class.forName(parameterClassName).newInstance();
 }
}

public class Generic extends GenericAbstract&lt;Foo&gt; {
}

public class Foo {
 public Foo() {
 System.out.println("Foo constructor...");
 }
}
</code></pre>

blocks|key|1296327|text|这是工厂实现，如Jon+Skeet+suggested|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1296328|interface+Factory<T>+{
++++T+factory();
}

class+Araba+{
++++//static+inner+class+for+Factory<T>+implementation
++++public+static+class+ArabaFactory+implements+Factory<Araba>+{
++++++++public+Araba+factory()+{
++++++++++++return+new+Araba();
++++++++}
++++}
++++public+String+toString()+{+return+"Abubeee";+}
}

class+Generic<T>+{
++++private+T+var;

++++Generic(Factory<T>+fact)+{
++++++++System.out.println("Constructor+with+Factory<T>+parameter");
++++++++var+=+fact.factory();
++++}
++++Generic(T+var)+{
++++++++System.out.println("Constructor+with+T+parameter");
++++++++this.var+=+var;
++++}
++++T+get()+{+return+var;+}
}

public+class+Main+{
++++public+static+void+main(String[]+string)+{
++++++++Generic<Araba>+gen+=+new+Generic<Araba>(new+Araba.ArabaFactory());
++++++++System.out.print(gen.get());
++++}
}|code-block|syntax|javascript|1296329|输出：|1296330|Constructor+with+Factory<T>+parameter
Abubeee|1296331|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/1090458/instantiating-a-generic-class-in-java/1090488#1090488^0|8|J|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

And this is the Factory implementation, as <a href="https://stackoverflow.com/questions/1090458/instantiating-a-generic-class-in-java/1090488#1090488">Jon Skeet suggested</a>:

<pre><code>interface Factory&lt;T&gt; {
 T factory();
}

class Araba {
 //static inner class for Factory&lt;T&gt; implementation
 public static class ArabaFactory implements Factory&lt;Araba&gt; {
 public Araba factory() {
 return new Araba();
 }
 }
 public String toString() { return "Abubeee"; }
}

class Generic&lt;T&gt; {
 private T var;

 Generic(Factory&lt;T&gt; fact) {
 System.out.println("Constructor with Factory&lt;T&gt; parameter");
 var = fact.factory();
 }
 Generic(T var) {
 System.out.println("Constructor with T parameter");
 this.var = var;
 }
 T get() { return var; }
}

public class Main {
 public static void main(String[] string) {
 Generic&lt;Araba&gt; gen = new Generic&lt;Araba&gt;(new Araba.ArabaFactory());
 System.out.print(gen.get());
 }
}
</code></pre>

Output:

<pre><code>Constructor with Factory&lt;T&gt; parameter
Abubeee
</code></pre>

blocks|key|1296431|text|来自https://stackoverflow.com/a/2434094/848072。你需要一个T类的默认构造函数。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1296432|import+java.lang.reflect.ParameterizedType;

class+Foo<T>+{
++
++public+bar()+{
++++ParameterizedType+superClass+=+(ParameterizedType)+getClass().getGenericSuperclass();
++++Class<T>+type+=+(Class<T>)+superClass.getActualTypeArguments()[0];
++++try+{
++++++T+t+=+(T)+type.getDeclaredConstructor().newInstance();
++++++//Do+whatever+with+t
++++}+catch+(Exception+e)+{
++++++//+Oops,+no+default+constructor
++++++throw+new+RuntimeException(e);
++++}+
++}
}|code-block|syntax|javascript|1296433|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/2434094/848072^0|2|16|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

From <a href="https://stackoverflow.com/a/2434094/848072">https://stackoverflow.com/a/2434094/848072</a>. You need a default constructor for T class.
<pre><code>import java.lang.reflect.ParameterizedType;

class Foo&lt;T&gt; {
 
 public bar() {
 ParameterizedType superClass = (ParameterizedType) getClass().getGenericSuperclass();
 Class&lt;T&gt; type = (Class&lt;T&gt;) superClass.getActualTypeArguments()[0];
 try {
 T t = (T) type.getDeclaredConstructor().newInstance();
 //Do whatever with t
 } catch (Exception e) {
 // Oops, no default constructor
 throw new RuntimeException(e);
 } 
 }
}
</code></pre>

blocks|key|1296464|text|我可以在JUnit测试设置中做到这一点。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1296465|我想测试一个Hibernate外观，所以我在寻找一种通用的方法来做这件事。请注意，facade还实现了一个通用接口。这里T是数据库类，U是主键。Ifacade<T,U>是用主键U访问数据库对象T的外观。|offset|length|style|CODE|1296466|public+abstract+class+GenericJPAController<T,+U,+C+extends+IFacade<T,U>>

{
++++protected+static+EntityManagerFactory+emf;

++++/*+The+properties+definition+is+straightforward*/
++++protected+T+testObject;
++++protected+C+facadeManager;

++++@BeforeClass
++++public+static+void+setUpClass()+{


++++++++try+{
++++++++++++emf+=+Persistence.createEntityManagerFactory("my+entity+manager+factory");

++++++++}+catch+(Throwable+ex)+{
++++++++++++System.err.println("Failed+to+create+sessionFactory+object."+%2B+ex);
++++++++++++throw+new+ExceptionInInitializerError(ex);
++++++++}

++++}

++++@AfterClass
++++public+static+void+tearDownClass()+{
++++}

++++@Before
++++public+void+setUp()+{
++++/*+Get+the+class+name*/
++++++++String+className+=+((ParameterizedType)+getClass().getGenericSuperclass()).getActualTypeArguments()[2].getTypeName();

++++++++/*+Create+the+instance+*/
++++++++try+{
++++++++++++facadeManager+=+(C)+Class.forName(className).newInstance();
++++++++}+catch+(ClassNotFoundException+%7C+InstantiationException+%7C+IllegalAccessException+ex)+{
++++++++++++Logger.getLogger(GenericJPAController.class.getName()).log(Level.SEVERE,+null,+ex);
++++++++}
++++++++createTestObject();
++++}

++++@After
++++public+void+tearDown()+{
++++}

++++/**
+++++*+Test+of+testFindTEntities_0args+method,+of+class
+++++*+GenericJPAController<T,+U,+C+extends+IFacade<T,U>>.
+++++*+@throws+java.lang.ClassNotFoundException
+++++*+@throws+java.lang.NoSuchMethodException
+++++*+@throws+java.lang.InstantiationException
+++++*+@throws+java.lang.IllegalAccessException
+++++*/
++++@Test
++++public+void++testFindTEntities_0args()+throws+ClassNotFoundException,+NoSuchMethodException,+InstantiationException,+IllegalAccessException+{

++++++++/*+Example+of+instance+usage.+Even+intellisense+(NetBeans)+works+here!*/
++++++++try+{
++++++++++++List<T>+lista+=+(List<T>)+facadeManager.findAllEntities();
++++++++++++lista.stream().forEach((ct)+->+{
++++++++++++++++System.out.println("Find+all:+"+%2B+stringReport());
++++++++++++});
++++++++}+catch+(Throwable+ex)+{
++++++++++++System.err.println("Failed+to+access+object."+%2B+ex);
++++++++++++throw+new+ExceptionInInitializerError(ex);
++++++++}
++++}


++++/**
+++++*
+++++*+@return
+++++*/
++++public+abstract+String+stringReport();

++++protected+abstract+T+createTestObject();
++++protected+abstract+T+editTestObject();
++++protected+abstract+U+getTextObjectIndex();
}|code-block|syntax|javascript|1296467|entityMap^0|0|20|C|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|$]]

I could do this in a JUnit Test Setup.

I wanted to test a Hibernate facade so I was looking for a generic way to do it. Note that the facade also implements a generic interface. Here T is the database class and U the primary key. 
<code>Ifacade&lt;T,U&gt;</code> is a facade to access the database object T with the primary key U.

<pre><code>public abstract class GenericJPAController&lt;T, U, C extends IFacade&lt;T,U&gt;&gt;

{
 protected static EntityManagerFactory emf;

 /* The properties definition is straightforward*/
 protected T testObject;
 protected C facadeManager;

 @BeforeClass
 public static void setUpClass() {


 try {
 emf = Persistence.createEntityManagerFactory("my entity manager factory");

 } catch (Throwable ex) {
 System.err.println("Failed to create sessionFactory object." + ex);
 throw new ExceptionInInitializerError(ex);
 }

 }

 @AfterClass
 public static void tearDownClass() {
 }

 @Before
 public void setUp() {
 /* Get the class name*/
 String className = ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[2].getTypeName();

 /* Create the instance */
 try {
 facadeManager = (C) Class.forName(className).newInstance();
 } catch (ClassNotFoundException | InstantiationException | IllegalAccessException ex) {
 Logger.getLogger(GenericJPAController.class.getName()).log(Level.SEVERE, null, ex);
 }
 createTestObject();
 }

 @After
 public void tearDown() {
 }

 /**
 * Test of testFindTEntities_0args method, of class
 * GenericJPAController&lt;T, U, C extends IFacade&lt;T,U&gt;&gt;.
 * @throws java.lang.ClassNotFoundException
 * @throws java.lang.NoSuchMethodException
 * @throws java.lang.InstantiationException
 * @throws java.lang.IllegalAccessException
 */
 @Test
 public void testFindTEntities_0args() throws ClassNotFoundException, NoSuchMethodException, InstantiationException, IllegalAccessException {

 /* Example of instance usage. Even intellisense (NetBeans) works here!*/
 try {
 List&lt;T&gt; lista = (List&lt;T&gt;) facadeManager.findAllEntities();
 lista.stream().forEach((ct) -&gt; {
 System.out.println("Find all: " + stringReport());
 });
 } catch (Throwable ex) {
 System.err.println("Failed to access object." + ex);
 throw new ExceptionInInitializerError(ex);
 }
 }


 /**
 *
 * @return
 */
 public abstract String stringReport();

 protected abstract T createTestObject();
 protected abstract T editTestObject();
 protected abstract U getTextObjectIndex();
}
</code></pre>

blocks|key|1296539|text|对我有效的快速解决方案。我看到这个问题已经有了答案，这甚至可能不是最好的方法。另外，对于我的解决方案，您将需要Gson。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1296540|但是，我遇到了需要创建java.lang.reflect.Type类型泛型类的实例的情况。|style|CODE|1296541|下面的代码将创建一个实例变量为空的类的实例。|1296542|T+object+=+new+Gson().fromJson("{}",+myKnownType);|code-block|syntax|javascript|1296543|其中myKnownType是预先知道的，并通过TypeToken.getType()获得。|1296544|现在，您可以在此对象上设置适当的属性。再说一次，这可能不是最好的方法，但如果您需要的话，它可以作为一个快速解决方案。|1296545|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/google/gson^0|1J|4|0|0|B|M|0|0|0|2|B|N|J|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@$A|11|B|12|1|13]]|C|$]]|$1|D|3|E|5|6|7|14|8|@$A|15|B|16|F|G]]|9|@]|C|$]]|$1|H|3|I|5|6|7|17|8|@]|9|@]|C|$]]|$1|J|3|K|5|L|7|18|8|@]|9|@]|C|$M|N]]|$1|O|3|P|5|6|7|19|8|@$A|1A|B|1B|F|G]|$A|1C|B|1D|F|G]]|9|@]|C|$]]|$1|Q|3|R|5|6|7|1E|8|@]|9|@]|C|$]]|$1|S|3|-4|5|6|7|1F|8|@]|9|@]|C|$]]]|T|$U|$5|V|W|X|C|$Y|Z]]]]

Quick solution that worked for me.
I see there is already an answer for this and this may not even be the best way to go about it. Also, for my solution you'll need <a href="https://github.com/google/gson" rel="nofollow noreferrer">Gson</a>.

However, I ran into a situation where I needed to create an instance of a generic class of type <code>java.lang.reflect.Type</code>.

The following code will create an instance of the class you want with null instance variables.

<pre><code>T object = new Gson().fromJson("{}", myKnownType);
</code></pre>

Where <code>myKnownType</code> is known before hand and obtained via <code>TypeToken.getType()</code>.

You can now set appropriate properties on this object. Again, this may not be the best way to do this but it works as a quick solution if that's what you need.

blocks|key|1296580|text|对于Java+8+...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1296581|在https://stackoverflow.com/a/36315051/2648077+post上有一个很好的解决方案。|offset|length|1296582|这使用Java8+Supplier函数接口|style|CODE|1296583|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/36315051/2648077^0|0|1|18|0|0|9|8|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@$D|T|E|U|1|V]]|A|$]]|$1|F|3|G|5|6|7|W|8|@$D|X|E|Y|H|I]]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]]]

For Java 8 ....

There is a good solution at <a href="https://stackoverflow.com/a/36315051/2648077">https://stackoverflow.com/a/36315051/2648077</a> post.

This uses Java 8 <code>Supplier</code> functional interface

blocks|key|1296624|text|使用Constructor.newInstance方法。从Java9开始，为了增强编译器对实例化异常的识别能力，Class.newInstance方法已被弃用。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1296625|public+class+Foo<T>+{+++
++++public+Foo()
++++{
++++++++Class<T>+newT+=+null;+
++++++++instantiateNew(newT);
++++}

++++T+instantiateNew(Class<?>+clsT)
++++{
++++++++T+newT;
++++++++try+{
++++++++++++newT+=+(T)+clsT.getDeclaredConstructor().newInstance();
++++++++}+catch+(InstantiationException+%7C+IllegalAccessException+%7C+IllegalArgumentException
++++++++++++%7C+InvocationTargetException+%7C+NoSuchMethodException+%7C+SecurityException+e)+{
++++++++++++//+TODO+Auto-generated+catch+block
++++++++++++e.printStackTrace();
++++++++++++return+null;
++++++++}
++++++++return+newT;
++++}
}|code-block|syntax|javascript|1296626|entityMap^0|2|N|1K|H|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

Use The <code>Constructor.newInstance</code> method. The <code>Class.newInstance</code> method has been deprecated since Java 9 to enhance compiler recognition of instantiation exceptions.

<pre><code>public class Foo&lt;T&gt; { 
 public Foo()
 {
 Class&lt;T&gt; newT = null; 
 instantiateNew(newT);
 }

 T instantiateNew(Class&lt;?&gt; clsT)
 {
 T newT;
 try {
 newT = (T) clsT.getDeclaredConstructor().newInstance();
 } catch (InstantiationException | IllegalAccessException | IllegalArgumentException
 | InvocationTargetException | NoSuchMethodException | SecurityException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 return null;
 }
 return newT;
 }
}
</code></pre>

I know Java's generics are somewhat inferior to .Net's.

I have a generic class <code>Foo&lt;T&gt;</code>, and I really need to instantiate a <code>T</code> in <code>Foo</code> using a parameter-less constructor. How can one work around Java's limitation?

Instantiating a generic class in Java

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我知道Java的泛型比.Net的稍差一些。我有一个泛型类Foo<T>，并且我确实需要使用无参数构造函数在Foo中实例化一个T。如何绕过Java的限制？

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