/*
   * 有泛型的情况
   * 使得程序具有更好的可读性和安全性
   */
  private static void test1() throws Exception {
    // 代码更具有可读性.
    Generic<String> bc = new Generic();
    String s = "OK";
    File file = new File("e:/1.txt");
    // 问题:在添加元素时,会检查错误,只可以向数组列表中添加指定类的对象.
    bc.add(s);
    // 由于加入的元素不是String类型,故报错.
    // bc.add(file);//error  The method add(String) in the type Generic<String> is not applicable
    // for the arguments (File)

    /*
     * 不用强制转换
     * 擦除get的返回类型后将返回Object类型.编译器自动插入String的强制类型转换.
     * 也就说,编译器把这个方法调用翻译为两条虚拟机指令:
     * 		1.对原始方法get的调用.
     * 		2.将返回的Object类型强制转换为String类型.
     */
    String s1 = bc.get(0);
  }
Exemple #2
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  /**
   * An <b>opaque</b> class representing members of its enclosing <b>opaque</b> type.
   *
   * <p>Note that, this class is <b>opaque</b> but its constructors are all <b>internal</b>. This
   * class and the subclasses of this class are used to declare either <b>opaque</b> <tt>public</tt>
   * instance fields of the opaque type {@link js.Var.Member} or the <b>opaque</b> <tt>public</tt>
   * static fields of other <b>opaque</b> types while their constructors are used to define the
   * fields inside <b>opaque</b> classes. Under either circumstance, the field names must be exactly
   * same as the member names, as the <b>opaque</b> fields of <b>opaque</b> types are resolved by
   * re-compilers directly based on the field names.
   *
   * @author <a href="mailto:[email protected]">J.J.Liu (Jianjun Liu)</a> at <a
   *     href="http://www.jscripter.org" target="_blank">http://www.jscripter.org</a>
   * @javascript <b>Opaque</b> types can be resolved but no class objects for them can be created in
   *     the target codes. Re-compilers must exit with error on operations accessing that kind of
   *     class objects. Re-compilers must resolve an <b>opaque</b> instance field declared by this
   *     class in {@link js.Var.Member} or its subclasses to the JavaScript identifier:
   *     <pre>q.m</pre>
   *     where <tt>m</tt> is the identifier of the field name and <tt>q</tt> is the identifier
   *     resolved from the instance of the enclosing member. Re-compilers must resolve an
   *     <b>opaque</b> static field declared by this class in <b>opaque</b> types other than {@link
   *     js.Var.Member} and its subclasses to the JavaScript identifier:
   *     <pre>m</pre>
   *     where <tt>m</tt> is the identifier of the field name. And re-compilers must report error on
   *     the access to <b>opaque</b> fields declared by this class under any other circumstances.
   */
  public static class Member extends JsGlobal.RangeError.Prototype.Member {
    /**
     * Internally constructs a member based on a qualifying member.
     *
     * <p>This constructor is <b>internal</b> and only called inside of <b>opaque</b> or
     * <b>internal</b> classes or class members.
     *
     * <p>Note that, this constructor is <b>internal</b> but its declaring class is <b>opaque</b>.
     * This constructor is used to define <b>opaque</b> instance fields declared in the declaring
     * class of this constructor itself or its subclasses. Under this circumstance, the field names
     * must be exactly same as the member names, as the <b>opaque</b> instance fields of the
     * <b>opaque</b> type {@link js.Var.Member} or its subclasses are resolved by re-compilers
     * directly to their names appending to the name resolved from the specified qualifying member
     * with a dot in between.
     *
     * @param q A qualifying member
     * @param mid The ID of the member to construct
     * @since 1.0
     * @javascript Re-compilers must report error on the invocation to an <b>internal</b>
     *     constructor.
     */
    public Member(JsObject.Member q, Mid mid) {
      super(q, mid);
    }
    /**
     * Internally constructs a member without a qualifying member.
     *
     * <p>This constructor is <b>internal</b> and only called inside of <b>opaque</b> or
     * <b>internal</b> classes or class members.
     *
     * <p>Note that, this constructor is <b>internal</b> but its declaring class is <b>opaque</b>.
     * This constructor is used to define <b>opaque</b> static fields, declared in <b>opaque</b>
     * types other than the declaring class of this constructor itself and its subclasses. Under
     * this circumstance, the field names must be exactly same as the member names, as the
     * <b>opaque</b> static fields of <b>opaque</b> types are generally resolved by re-compilers
     * directly to identifiers of their names.
     *
     * @param mid The ID of the member to construct
     * @since 1.0
     * @javascript Re-compilers must report error on the invocation to an <b>internal</b>
     *     constructor.
     */
    public Member(Mid mid) {
      super(mid);
    }
    /**
     * Evaluates the property, represented by the current member instance, of the argument object.
     *
     * @param o The argument object
     * @return The value of the current member based on the object argument.
     * @since 1.0
     * @javascript Re-compilers must convert the instance invocation of this method into the
     *     JavaScript expression:
     *     <pre>o.m</pre>
     *     where <tt>m</tt> is the identifier name resolved from the current member instance of the
     *     invocation.
     */
    @Override
    public JsRangeError with(ObjectLike o) {
      return new JsRangeError(super.with(o));
    }

    /**
     * An <b>opaque</b> instance field defining a sub-member that is named by the name of this
     * field, qualified by the current member instance of the field, and to access the property of
     * the name on an object.
     *
     * <p>The <tt>constructor</tt> property of an object is a reference to the function that was the
     * constructor for that object.
     *
     * <p>A common use of the <tt>constructor</tt> property is to determine the type of unknown
     * objects. Given an unknown value, you can use the {@link js.Js#typeof(Object)} operation to
     * determine whether it is a primitive value or an object. If it is an object, you can use the
     * <tt>constructor</tt> property to determine what type of object it is.
     *
     * <p>Note, however, that while this technique works for the objects built into core JavaScript,
     * it is not guaranteed to work with host objects such as the <tt>window</tt> object of
     * client-side JavaScript. The default implementation of the <tt>toString()</tt> method provides
     * another way to determine the type of an unknown object.
     *
     * @since 1.0
     * @javascript Re-compilers must resolve the member of this instance field to the identifier of
     *     the field name appending to the identifier resolved from its qualifying member with a dot
     *     in between.
     */
    public final JsFunction.Member<JsRangeError> constructor =
        new JsFunction.Member<JsRangeError>(
            this, Members.constructor, Generic.get(JsRangeError.class));
  }
Exemple #3
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/**
 * An <b>opaque</b> class representing JavaScript <tt>RangeError</tt>.
 *
 * <p>An instance of the this class is thrown when a numeric value is not in its legal range. For
 * example, setting the length of an array to a negative number causes a <tt>RangeError</tt> to be
 * thrown.
 *
 * <p>In JS, to throw a value or object as a <tt>RuntimeException</tt>, see {@link
 * js.Js#err(Object)}.
 *
 * @author <a href="mailto:[email protected]">J.J.Liu (Jianjun Liu)</a> at <a
 *     href="http://www.jscripter.org" target="_blank">http://www.jscripter.org</a>
 * @see js.Js#err(Object)
 * @javascript <b>Opaque</b> types can be resolved but no class objects for them can be generated
 *     into the target codes. Re-compilers must exit with error on the operations of accessing that
 *     kind of class objects. The <tt>checkcast</tt> operation to the class literal of this
 *     interface must be ignored and <tt>instanceof</tt> to it always <tt>true</tt>.
 */
public class JsRangeError extends JsGlobal.RangeError.Prototype {
  /**
   * An <b>opaque</b> class representing members of its enclosing <b>opaque</b> type.
   *
   * <p>Note that, this class is <b>opaque</b> but its constructors are all <b>internal</b>. This
   * class and the subclasses of this class are used to declare either <b>opaque</b> <tt>public</tt>
   * instance fields of the opaque type {@link js.Var.Member} or the <b>opaque</b> <tt>public</tt>
   * static fields of other <b>opaque</b> types while their constructors are used to define the
   * fields inside <b>opaque</b> classes. Under either circumstance, the field names must be exactly
   * same as the member names, as the <b>opaque</b> fields of <b>opaque</b> types are resolved by
   * re-compilers directly based on the field names.
   *
   * @author <a href="mailto:[email protected]">J.J.Liu (Jianjun Liu)</a> at <a
   *     href="http://www.jscripter.org" target="_blank">http://www.jscripter.org</a>
   * @javascript <b>Opaque</b> types can be resolved but no class objects for them can be created in
   *     the target codes. Re-compilers must exit with error on operations accessing that kind of
   *     class objects. Re-compilers must resolve an <b>opaque</b> instance field declared by this
   *     class in {@link js.Var.Member} or its subclasses to the JavaScript identifier:
   *     <pre>q.m</pre>
   *     where <tt>m</tt> is the identifier of the field name and <tt>q</tt> is the identifier
   *     resolved from the instance of the enclosing member. Re-compilers must resolve an
   *     <b>opaque</b> static field declared by this class in <b>opaque</b> types other than {@link
   *     js.Var.Member} and its subclasses to the JavaScript identifier:
   *     <pre>m</pre>
   *     where <tt>m</tt> is the identifier of the field name. And re-compilers must report error on
   *     the access to <b>opaque</b> fields declared by this class under any other circumstances.
   */
  public static class Member extends JsGlobal.RangeError.Prototype.Member {
    /**
     * Internally constructs a member based on a qualifying member.
     *
     * <p>This constructor is <b>internal</b> and only called inside of <b>opaque</b> or
     * <b>internal</b> classes or class members.
     *
     * <p>Note that, this constructor is <b>internal</b> but its declaring class is <b>opaque</b>.
     * This constructor is used to define <b>opaque</b> instance fields declared in the declaring
     * class of this constructor itself or its subclasses. Under this circumstance, the field names
     * must be exactly same as the member names, as the <b>opaque</b> instance fields of the
     * <b>opaque</b> type {@link js.Var.Member} or its subclasses are resolved by re-compilers
     * directly to their names appending to the name resolved from the specified qualifying member
     * with a dot in between.
     *
     * @param q A qualifying member
     * @param mid The ID of the member to construct
     * @since 1.0
     * @javascript Re-compilers must report error on the invocation to an <b>internal</b>
     *     constructor.
     */
    public Member(JsObject.Member q, Mid mid) {
      super(q, mid);
    }
    /**
     * Internally constructs a member without a qualifying member.
     *
     * <p>This constructor is <b>internal</b> and only called inside of <b>opaque</b> or
     * <b>internal</b> classes or class members.
     *
     * <p>Note that, this constructor is <b>internal</b> but its declaring class is <b>opaque</b>.
     * This constructor is used to define <b>opaque</b> static fields, declared in <b>opaque</b>
     * types other than the declaring class of this constructor itself and its subclasses. Under
     * this circumstance, the field names must be exactly same as the member names, as the
     * <b>opaque</b> static fields of <b>opaque</b> types are generally resolved by re-compilers
     * directly to identifiers of their names.
     *
     * @param mid The ID of the member to construct
     * @since 1.0
     * @javascript Re-compilers must report error on the invocation to an <b>internal</b>
     *     constructor.
     */
    public Member(Mid mid) {
      super(mid);
    }
    /**
     * Evaluates the property, represented by the current member instance, of the argument object.
     *
     * @param o The argument object
     * @return The value of the current member based on the object argument.
     * @since 1.0
     * @javascript Re-compilers must convert the instance invocation of this method into the
     *     JavaScript expression:
     *     <pre>o.m</pre>
     *     where <tt>m</tt> is the identifier name resolved from the current member instance of the
     *     invocation.
     */
    @Override
    public JsRangeError with(ObjectLike o) {
      return new JsRangeError(super.with(o));
    }

    /**
     * An <b>opaque</b> instance field defining a sub-member that is named by the name of this
     * field, qualified by the current member instance of the field, and to access the property of
     * the name on an object.
     *
     * <p>The <tt>constructor</tt> property of an object is a reference to the function that was the
     * constructor for that object.
     *
     * <p>A common use of the <tt>constructor</tt> property is to determine the type of unknown
     * objects. Given an unknown value, you can use the {@link js.Js#typeof(Object)} operation to
     * determine whether it is a primitive value or an object. If it is an object, you can use the
     * <tt>constructor</tt> property to determine what type of object it is.
     *
     * <p>Note, however, that while this technique works for the objects built into core JavaScript,
     * it is not guaranteed to work with host objects such as the <tt>window</tt> object of
     * client-side JavaScript. The default implementation of the <tt>toString()</tt> method provides
     * another way to determine the type of an unknown object.
     *
     * @since 1.0
     * @javascript Re-compilers must resolve the member of this instance field to the identifier of
     *     the field name appending to the identifier resolved from its qualifying member with a dot
     *     in between.
     */
    public final JsFunction.Member<JsRangeError> constructor =
        new JsFunction.Member<JsRangeError>(
            this, Members.constructor, Generic.get(JsRangeError.class));
  }

  /**
   * Casts an <b>opaque</b> object to the current <b>opaque</b> type by wrapping it with the
   * wrapping constructor.
   *
   * @param var The argument of an <b>opaque</b> object.
   * @since 1.0
   * @javascript Re-compilers must ignore the construction operation of this constructor, that is,
   *     replacing it with its only argument.
   */
  public JsRangeError(JsObject var) {
    super(var);
  }

  /**
   * An <b>opaque</b> static field defining a member that is named by the field name without a
   * qualifying member and to access the property of the name on an object.
   *
   * <p>The <tt>constructor</tt> property of an object is a reference to the function that was the
   * constructor for that object.
   *
   * <p>A common use of the <tt>constructor</tt> property is to determine the type of unknown
   * objects. Given an unknown value, you can use the {@link js.Js#typeof(Object)} operation to
   * determine whether it is a primitive value or an object. If it is an object, you can use the
   * <tt>constructor</tt> property to determine what type of object it is.
   *
   * <p>Note, however, that while this technique works for the objects built into core JavaScript,
   * it is not guaranteed to work with host objects such as the <tt>window</tt> object of
   * client-side JavaScript. The default implementation of the <tt>toString()</tt> method provides
   * another way to determine the type of an unknown object.
   *
   * @since 1.0
   * @javascript Re-compilers must resolve the member of this static field to the identifier of the
   *     field name.
   */
  public static final JsFunction.Member<JsRangeError> constructor =
      new JsFunction.Member<JsRangeError>(Members.constructor, Generic.get(JsRangeError.class));

  /**
   * Returns the primitive value associated with the current instance, if there is one. This
   * invocation simply returns the instance itself for the current instance is an object and there
   * is no primitive value for it.
   *
   * @return The current object itself.
   * @since 1.0
   * @javascript Re-compilers must convert the instance invocation of this method directly into a
   *     JavaScript invocation on its current object instance without changing the method name, but
   *     expanding variable arguments, if any, into comma-separated values.
   */
  @Override
  public JsRangeError valueOf() {
    return new JsRangeError((JsObject) var().valueOf());
  }
}