Question

尝试从yaml加载数据并创建以下对象：

问题：无法将yaml映射到Object，当我尝试将其始终抛出异常时：java.util.LinkedHashMap无法转换为com.heraizen.DataConfig $ Data

Map<String,List<Data>> map;

代码段：

public class DataConfig {
private Map<String, List<Data>> heros = new HashMap<String, List<Data>>();

public static class Data {
    private String name;
    private String uri;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getUri() {
        return uri;
    }

    public void setUri(String uri) {
        this.uri = uri;
    }

    @Override
    public String toString() {
        return "Data [name=" + name + ", uri=" + uri + "]";
    }

}

public Map<String, List<Data>> getHeros() {
    return heros;
}

public void setHeros(Map<String, List<Data>> heros) {
    this.heros = heros;
}

Yaml：

  --- 
 heros: 
   one:

     - name: h1
       url: hu2
     - name: h2
       url: hu22
  two: 
    - name: h3
      url: hu3

构造对象：

   Yaml yaml = new Yaml(new Constructor(DataConfig.class));

   DataConfig retValue = (DataConfig) yaml.load(new FileInputStream("one.yaml"));
   retValue.getHeros().entrySet().forEach(ele->{
       System.out.println(ele.getKey()+" "+ele.getValue().get(0).getName());
   });
    System.out.println(retValue);

Answer 1

由于//changelogs.blade.php var table = $('.data-table').DataTable({ processing: true, serverSide: true, ajax: "{{ route('change_logs.index') }}", columns: [ //{data: 'DT_RowIndex', name: 'DT_RowIndex'}, {data: 'id', name: 'change_logs.id'}, {data: 'user.name', name: 'user.name'}, {data: 'user.username', name: 'user.username'}, {data: 'sector.location.location_name', name: 'sector.location.location_name'}, {data: 'sector.sector_name', name: 'sector.sector_name'}, {data: 'layer_category.layer.layer_name', name: 'layer_category.layer.layer_name'}, {data: 'layer_category.category_name', name: 'layer_category.category_name'}, {data: 'object_name', name: 'object_name'}, {data: 'operation.operation_name', name: 'operation.operation_name'}, {data: 'action', name: 'action', orderable: false, searchable: false}, ] }); //controller $data = ChangeLog::with('user','sector','operation','layer_category' )->select('change_logs.*'); return Datatables::of($data) //class ChangeLog <?php namespace App; use Illuminate\Database\Eloquent\Model; class ChangeLog extends Model { protected $fillable = [ 'username', 'sector_id','operation_id', 'layer_category_id', 'object_name' ]; protected $hidden = [ ]; public function location() { return $this->belongsTo('App\Location'); } public function user() { //return $this->belongsTo('App\User'); return $this->belongsTo('App\User', 'username', 'username'); } public function sector() { return $this->belongsTo('App\Sector')->with('location'); } public function operation() { return $this->belongsTo('App\Operation'); } public function layer_category() { return $this->belongsTo('App\LayerCategory')->with('layer'); } } //class Sector <?php namespace App; use Illuminate\Database\Eloquent\Model; class Sector extends Model { protected $fillable = [ 'sector_name','location_id', ]; protected $hidden = [ ]; public function location() { return $this->belongsTo('App\Location'); } } //class Location <?php namespace App; use Illuminate\Database\Eloquent\Model; class Location extends Model { protected $fillable = [ 'location_name', ]; protected $hidden = [ ]; public function sectors() { return $this->hasMany('App\Sector'); } }不是DataConfig的子类型或超类型，因此无法在其中使用强制类型转换。我对yaml不熟悉，但是我可以假设方法LinkedHashMap从您的异常描述中返回了yaml.load()。

尝试编写属于LinkedHashMap的静态方法，该方法将DataConfig转换为LinkedHashMap：

DataConfig

如何使用snakeyaml从yaml获取Map <String，List <Data >>

1 个答案: