Netlogo 扩展：比较字符串列表

Question

我正在尝试编写我的第一个 Netlogo 扩展，希望它可以与字符串列表进行比较。由于我是编写扩展的新手并且对编程了解不多 Java 我希望得到帮助。

到目前为止我的代码是：

package org.nlogo.extensions.string;

import org.nlogo.api.Argument;
import org.nlogo.api.Context;
import org.nlogo.api.DefaultReporter;
import org.nlogo.api.ExtensionException;
import org.nlogo.api.LogoException;
import org.nlogo.api.Syntax;
import org.nlogo.api.LogoListBuilder;
import org.nlogo.api.LogoList;


public class Matching2 extends DefaultReporter{

@Override
public Syntax getSyntax(){
    return Syntax.reporterSyntax(new int[] { Syntax.ListType(), Syntax.ListType()  },
                                 Syntax.ListType());
}


@Override
public Object report(Argument args[], Context context)
        throws ExtensionException, LogoException
    {
        LogoList input1 = args[0].getList() ;
        LogoList input2 = args[1].getList();
        return input1.retainAll(input2);

    }

}

但是，当我尝试运行模型时，我只得到一个错误...

提前致谢。

编辑：

error (UnsupportedOperationException)
while observer running SHOW
called by procedure CHECK-POTENTIAL-WORDS
called by procedure GO
called by Button 'go one time step'

NetLogo is unable to supply you with more details about this error.Please report the problem at https://github.com/NetLogo/NetLogo/issues, or to bugs@ccl.northwestern.edu, and paste the contents of this window into your report.

java.lang.UnsupportedOperationException at org.nlogo.api.LogoList.org$nlogo$api$LogoList$$unsupported(LogoList.scala:67)
at org.nlogo.api.LogoList$Iterator.remove(LogoList.scala:64)
at org.nlogo.api.LogoList$Iterator.remove(LogoList.scala:54)
at java.util.AbstractCollection.retainAll(AbstractCollection.java:410)
at org.nlogo.extensions.string.Matching2.report(Matching2.java:28)
at org.nlogo.prim._externreport.report(_externreport.java:50)
at org.nlogo.prim.etc._show.perform(_show.scala:13)
at org.nlogo.nvm.Context.stepConcurrent(Context.java:91)
at org.nlogo.nvm.ConcurrentJob.step(ConcurrentJob.java:82)
at     org.nlogo.job.JobThread.org$nlogo$job$JobThread$$runPrimaryJobs(JobThread.scala:143)
 at org.nlogo.job.JobThread$$anonfun$run.apply$mcV$sp(JobThread.scala:78)
 at org.nlogo.job.JobThread$$anonfun$run.apply(JobThread.scala:76)
 at org.nlogo.job.JobThread$$anonfun$run.apply(JobThread.scala:76)
 at scala.util.control.Exception$Catch.apply(Exception.scala:88)
 at org.nlogo.util.Exceptions$.handling(Exceptions.scala:41)
 at org.nlogo.job.JobThread.run(JobThread.scala:75)

Answer 1

List 接口的 LogoList 实现不支持 retainAll() 方法 - 也就是说，因为该方法的默认实现在 AbstractCollection 中使用迭代器的 remove() 方法，即 unsupported by LogoList - 请在此处查看其源代码：https://github.com/NetLogo/NetLogo/blob/c56cffd5b12cf135efc4c3640b3cc0d5dc2acc3c/parser-core/src/main/core/LogoList.scala

解决方法：使用支持此操作的实现创建您自己的列表对象（例如 ArrayList）：

List input1 = new ArrayList(args[0].getList());
List input2 = new ArrayList(args[1].getList());

input1.retainAll(input2);
return input1;

但如果您需要 return 一个 LogoList，这可能行不通 - 试试这个：

return new LogoList(input1);

Netlogo 扩展：比较字符串列表

Netlogo Extension: Comparing Lists of Strings

java

netlogo