Question

我已经继承了Struts 2应用程序，并且尝试对其进行一些增强。要求是一次上传多个文档。每个文档都需要：描述，文档类型，文档类别和所述文档。我的Form类有一个ID表示代表文档也应该关联的父记录，还有一个ArrayList of Document对象。由于我不知道将要上传多少文档，并且每个父对象的文档数量都不同，因此我需要一种动态允许文档集上传的方法。

我的表单属性最终看起来像这样：

documents[0].category
documents[0].inFile
documents[0].docType
documents[0].description
documents[1].category
documents[1].inFile
documents[1].docType
documents[1].description

但是，当执行“保存”操作时，我的文档集合始终为null。

我的表单类是通过这种方式设置的。

public final class JobdocuwareMultiForm extends BaseForm {

/**
 *
 */
private static final long serialVersionUID = 1L;

private String _action;

private java.lang.String jobhdrId;

private ArrayList<JobdocForm> documents;

public String getAction() {
    return _action;
}

public void setAction(String _action) {
    this._action = _action;
}


private void addErrorIfBlank(ActionErrors errors, String fieldName,
                             String fieldValue, String message) {
    if (fieldValue == null || fieldValue.trim().equals("")) {
        errors.add(fieldName, new ActionMessage(message));
    }
}

public void setDocuments(ArrayList<JobdocForm> documents){
    this.documents = documents;
}

public JobdocForm getDocument(int index){
    return documents.get(index);
}

public ArrayList<JobdocForm> getDocuments(){
    return documents;
}

public String getJobhdrId () { return jobhdrId; }
public void setJobhdrId (String jobhdrId) { this.jobhdrId = jobhdrId; }

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {

    // do not vaildate if Delete Action
    if (_action == null || _action.equals("Delete")) return null;

    ActionErrors errors = new ActionErrors();

    for (JobdocForm doc:documents) {

        addErrorIfBlank(errors, "description", doc.getDescription(), "error.description.required");
        addErrorIfBlank(errors, "doctype", doc.getDoctype(), "error.documenttype.required");

        if (_action.equals("Create")) {
            addErrorIfBlank(errors, "infile", doc.getInfile().getFileName(), "error.document.required");
        }
    }
    // Perform validator framework validations
    return errors;

}

/**
 * Returns an array of keys, representing values that should not be
 * populated for the current form instance. Subclasses that override
 * this method to provide additional keys to be skipped should be
 * sure to call <code>super</code>
 *
 * @return an array of keys to be skipped
 */
@SuppressWarnings("rawtypes")
protected ArrayList keysToSkip() {
    ArrayList keysToSkip = super.keysToSkip();      

    return keysToSkip;
    }

}

尝试找到解决方案时，我遇到了这个post，其中提到“应该确保在构造函数和reset方法中初始化List”。否则，您将得到意想不到的结果。由于我还是Struts 2的新手，所以我随时尝试添加

JobdocuwareMultiForm(){
super();
this.docuemnts = new ArrayList<JobdocuwareForm>();
}

它根本无法加载表格。我或者被重定向到我的登录屏幕，或者一直有用的An unexpected error has occured消息。放置断点无济于事，因为它似乎无法进入Action类。

如何以动作形式初始化集合

0 个答案: