在Java中，可以使用ArrayAdapter类来实现搜索类名本身而不是用户的功能。下面是一个使用ArrayAdapter的代码示例：

import android.content.Context;
import android.widget.ArrayAdapter;
import android.widget.Filter;
import android.widget.Filterable;

import java.util.ArrayList;
import java.util.List;

public class ClassNameAdapter extends ArrayAdapter implements Filterable {

    private List originalData;
    private List filteredData;
    private ClassNameFilter filter;

    public ClassNameAdapter(Context context, int resource, List data) {
        super(context, resource, data);
        this.originalData = data;
        this.filteredData = data;
        this.filter = new ClassNameFilter();
    }

    @Override
    public int getCount() {
        return filteredData.size();
    }

    @Override
    public String getItem(int position) {
        return filteredData.get(position);
    }

    @Override
    public Filter getFilter() {
        return filter;
    }

    private class ClassNameFilter extends Filter {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults results = new FilterResults();
            List filteredList = new ArrayList<>();

            if (constraint == null || constraint.length() == 0) {
                // 如果搜索条件为空或长度为0，则返回原始数据
                filteredList.addAll(originalData);
            } else {
                String filterPattern = constraint.toString().toLowerCase().trim();

                // 遍历原始数据，找到匹配搜索条件的类名
                for (String className : originalData) {
                    if (className.toLowerCase().contains(filterPattern)) {
                        filteredList.add(className);
                    }
                }
            }

            results.values = filteredList;
            results.count = filteredList.size();
            return results;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            filteredData = (List) results.values;
            notifyDataSetChanged();
        }
    }
}

使用上述代码，你可以创建一个ClassNameAdapter对象并将其设置为你的列表视图的适配器。当用户输入搜索关键字时，ArrayAdapter将根据用户输入的关键字过滤类名，并更新列表视图显示过滤后的结果。