java - 将三个通用数组列表合并为一个

Question

我有三个泛型类型的列表。我想将它们组合成一个列表并从函数返回，但我不知道如何将其转换为一个对象。这是我的代码......

public class WrapUpCodes 
{

public Map<Long, W_Code> codes= new HashMap<>();
public Map<Long, S_Services> services= new HashMap<>();
public Map<Long, S_Group> skills= new HashMap<>();

public WrapUpCodes(){}

public WrapUpCodes(String dnis, String skillgroup)
{
    populateResultString( dnis, skillgroup);
}

public void populateResultString(String dnis, String skillgroup)
{
    DBCPSource conn= new DBCPSource();
    String[] Res = null;
    try 
    {
        Res = conn.GetwrapUpCodes(dnis, skillgroup);
    } 
    catch (Exception e) 
    {
        e.printStackTrace();
    }       
    String code[] =Res[0].split(",");
    long keyValue = 1;

    for(int k=0; k<code.length; k++)
    {
        codes.put(keyValue, new W_Code (code[k]));
        keyValue = keyValue+1;
    }

    String ser [] = Res[1].split(",");
    keyValue=1;

    for(int j=0; j<ser.length; j++)
    {
        services.put(keyValue, new S_Services(ser[j]));
        keyValue= keyValue+1;
    }

    String SG [] = Res[2].split(",");
    keyValue=1;

    for(int j=0; j<SG.length; j++)
    {
        skills.put(keyValue, new S_Group(SG[j]));
        keyValue= keyValue+1;
    }

}

public List<List<String>> getAllCodes()
{
    ArrayList<S_Group> SG= new ArrayList<S_Group>(skills.values());
    ArrayList<W_Code> WC= new ArrayList<W_Code> (codes.values());
    ArrayList<S_Services> SER= new ArrayList<S_Services>   (services.values());     
}       
}

I am getting problem in this function.

public List<List<String>> getAllCodes()
{
    ArrayList<S_Group> SG= new ArrayList<S_Group>(skills.values());
    ArrayList<W_Code> WC= new ArrayList<W_Code> (codes.values());
    ArrayList<S_Services> SER= new ArrayList<S_Services>    (services.values());        
}       
}

我想返回所有三个 ArraList。谁能帮我解决这个问题。

Answer 1

返回数据对象:

public static class CodeData {
    public final ArrayList<S_Group> groups = new ArrayList<>();
    public final ArrayList<W_Code> codes = new ArrayList<>();
    public final ArrayList<S_Services> services = new ArrayList<>();
}

public CodeData getAllCodes()
{
    CodeData data = new CodeData();
    data.groups.addAll(skills.values());
    data.codes.addAll(codes.values());
    data.services.addAll(services.values());
    return data;
}