struts2 无法上传文件。无效的字段值

Question

当我尝试在 struts2 中上传文件时，我看到验证错误：“上传”字段的字段值无效。 在 JBoss 控制台中，我得到：

10:37:56,140 WARN  [OgnlValueStack] Error setting expression 'upload' with value '[Ljava.lang.String;@17c7b19'
ognl.MethodFailedException: Method "setUpload" failed for object bm.action.content.SaveNewBannerAction@13ebb53 [java.lang.NoSuchMethodException: bm.action.content.SaveNewBannerAction.setUpload([Ljava.lang.String;)]
    at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1289)
    at ognl.OgnlRuntime.setMethodValue(OgnlRuntime.java:1478)
    at ognl.ObjectPropertyAccessor.setPossibleProperty(ObjectPropertyAccessor.java:85)
    at ognl.ObjectPropertyAccessor.setProperty(ObjectPropertyAccessor.java:162)
...
...
Caused by: java.lang.NoSuchMethodException: bm.action.content.SaveNewBannerAction.setUpload([Ljava.lang.String;)
    at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1230)

/-- Encapsulated exception ------------\
java.lang.NoSuchMethodException: bm.action.content.SaveNewBannerAction.setUpload([Ljava.lang.String;)
    at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1230)
    at ognl.OgnlRuntime.setMethodValue(OgnlRuntime.java:1478)
    at ognl.ObjectPropertyAccessor.setPossibleProperty(ObjectPropertyAccessor.java:85)
    at ognl.ObjectPropertyAccessor.setProperty(ObjectPropertyAccessor.java:162)

我的jsp：

<div class="v4DDfiltering">
    <s:fielderror/>
    <s:form id="saveNewBannerForm" name="saveNewBannerForm"
        action="SaveNewBannerAction" theme="simple" method="POST" enctype="multipart/form-data">
...
        <div class="OneFilteringRow">
            <s:label for="upload" value="Plik:*" />
            <s:file id="upload" name="upload"/>
        </div>
...
        <div class="OneFilteringRow">
            <s:url id="saveNewBannerUrl" action="SaveNewBannerAction" />

            <sj:a href="%{saveNewBannerUrl}" targets="messagesDiv"
                formIds="saveNewBannerForm">
                Save
            </sj:a>

        </div>
    </s:form>
</div>

我的动作类 SaveNewBannerAction.java

public class SaveNewBannerAction extends BaseAction {
    private static final long serialVersionUID = 1L;

    private static final Log LOG = LogFactory.getLog(SaveNewBannerAction.class);

    private boolean validate = true;

    private File upload;// The actual file
    private String uploadContentType; // The content type of the file
    private String uploadFileName; // The uploaded file name
    private String fileCaption;// The caption of the file entered by user
        ...

    public File getUpload() {
        return upload;
    }

    public void setUpload(File upload) {
        this.upload = upload;
    }

    public String getUploadContentType() {
        return uploadContentType;
    }

    public void setUploadContentType(String uploadContentType) {
        this.uploadContentType = uploadContentType;
    }

    public String getUploadFileName() {
        return uploadFileName;
    }

    public void setUploadFileName(String uploadFileName) {
        this.uploadFileName = uploadFileName;
    }

    public String getFileCaption() {
        return fileCaption;
    }

    public void setFileCaption(String fileCaption) {
        this.fileCaption = fileCaption;
    }
    @Override
    public void validate() {
        LOG.info("Enter: validate()");

        LOG.info("VALIDATE FIELDS");
        ...
        if(upload == null) {
            addFieldError("upload",
                    "Proszę uzupełnić pole: plik.");
            validate = false;
        } else {
            if(!uploadContentType.contains("image")) {
                addFieldError("upload",
                        "Wprowadzono niepoprawny format pliku. Plik musi być obrazkiem.");
                validate = false;
            }
        }

        LOG.info("Exit: validate()");
    }

我会很感激你的帮助。

Answer 1

你的jsp应该是这样的：

<div class="v4DDfiltering">
    <s:fielderror/>
    <s:form id="saveNewBannerForm" name="saveNewBannerForm"
        action="SaveNewBannerAction" theme="simple" method="POST" enctype="multipart/form-data">
...
        <div class="OneFilteringRow">
            <s:label for="upload" value="Plik:*" />
            <s:file id="upload" name="upload"/>
        </div>
...
        <div class="OneFilteringRow">
            <sj:submit targets="messagesDiv"/>
        </div>
    </s:form>
</div>

或：

<div class="v4DDfiltering">
    <s:fielderror/>
    <s:form id="saveNewBannerForm" name="saveNewBannerForm"
        action="SaveNewBannerAction" theme="simple" method="POST" enctype="multipart/form-data">
...
        <div class="OneFilteringRow">
            <s:label for="upload" value="Plik:*" />
            <s:file id="upload" name="upload"/>
        </div>
...
    </s:form>
    <sj:a targets="messagesDiv" formIds="saveNewBannerForm">Save</sj:a>
</div>