英文:
Initialize A Class by Class.forName with Array type parameters
问题
我有一个带有构造函数的类，我需要通过名称进行初始化。
public class Wall extends Tile
{
public Wall(double x, double y, double[] data)
{
super();
}
}
Tile是一个抽象类，它的构造函数是空的。
我可以使用以下方式初始化这个类：
Class.forName("Wall").newInstance();
如果我想在初始化类时传递参数，我可以使用以下方式：
Constructor<?> c = Class.forName("Wall").getConstructor(param);
c.newInstance(参数值，例如 "String");
至于`param`，它取决于您要传递的参数类型。
`int`：`Integer.TYPE`
`double`：`Double.TYPE`
`String`：`String.class`
这篇stackoverflow上的帖子对我理解这些参数有所帮助
https://stackoverflow.com/questions/5658182/initializing-a-class-with-class-forname-and-which-have-a-constructor-which-tak
但我有一个问题，我怎么传递数组参数，比如`double[]`？
我尝试过`Double[].class`，但那会抛出`ThreadNotFoundException`错误。
任何帮助将不胜感激。
英文:
I have a class with a constructor that I need to initialize by name.
public class Wall extends Tile
{
public Wall(double x, double y, double[] data)
{
super();
}
}
the Tile is an abstract class, and it's constructor is empty.
I can initialize this class with
Class.forName("Wall").newInstance();
And if I want to pass Parameters through when I initiate the class, I can use
Constructor<?> c = Class.forName("Wall").getConstructor(param);
c.newInstance(Paramater values ie. "String");
As for the param, it depends on what type of parameter you are passing through.
int: Integer.TYPE
double : Double.TYPE
String : String.class
this post on stackoverflow helped me with those parameters
https://stackoverflow.com/questions/5658182/initializing-a-class-with-class-forname-and-which-have-a-constructor-which-tak
But the question I have is how can I pass through Array parameters. ie a double[]?
I've tried Double[].class, but that threw a ThreadNotFoundException.
Any help would be appreciated.
答案1
得分: 1
可能有更好的方法。但我已经测试过了，它可以工作：
Constructor<?> constr = Class.forName("Wall").getDeclaredConstructor(Double.TYPE, Double.TYPE, (new double[] {}).getClass());
double x = 1;
double y = 2;
double[] data = new double[] {1, 2, 3, 4};
Wall obj = (Wall) constr.newInstance(x, y, data);
英文:
It might there be a better way. But I've tested that and it works:
Constructor<?> constr = Class.forName("Wall").getDeclaredConstructor(Double.TYPE, Double.TYPE, (new double[] {}).getClass());
double x = 1;
double y = 2;
double[] data = new double[] {1, 2, 3, 4};
Wall obj = (Wall) constr.newInstance( x , y, data );
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