不能Marshal java.lang.String

Question

这是我的困境:

我有一个dto类,用于从/向XML来回编组.

这是诀窍:由于我们的项目处理的dto类的数量是具有复数outter标记的集合,我决定创建一个委托集合,允许我从其中一个类中轻松地将它们转换为Collection并获取随之而来的便利(迭代,添加等).

在我们的项目中,我们有编组测试来清除注释错误等.以下是我的故障代码.

问题:根据封送程序,如果我扩展此QuickCollection,我会收到以下错误.当使用CXF将对象解组为x​​ml作为对Web服务请求的响应时,它将失败.确切错误:com.sun.istack.SAXException2:无法封装类型"java.lang.String"作为元素,因为它缺少@XmlRootElement注释

当它在测试中用JAXB进行编组/解组时它很好.当使用相同的QuickCollection来编组第三方使用spring RestOperations的结果并且工作正常

心灵螺丝:当我删除继承并将集合作为私人成员管理时,一切正常!

这对我来说不是一种感觉,因为我在两种情况下都会返回确切的数据类型.

以下是所有相关代码.

这是Inherited委托类.

    public class QuickCollection<T> implements Collection<T> {
    // to be set if needed after instantiation. To behave like a normal collection, we set it to something safe
    protected Collection<T> delegate = Collections.emptySet();

    public QuickCollection() {
    }

    public QuickCollection(Collection<T> delegate) {
        this.delegate = delegate;
    }

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

    @Override
    public boolean isEmpty() {
        return delegate.isEmpty();
    }

    @Override
    public boolean contains(Object o) {
        return delegate.contains(o);
    }

    @Override
    public Iterator<T> iterator() {
        return delegate.iterator();
    }

    @Override
    public Object[] toArray() {
        return delegate.toArray();
    }

    @Override
    public <T> T[] toArray(T[] a) {
        return delegate.toArray(a);
    }

    @Override
    public boolean add(T t) {
        return delegate.add(t);
    }

    @Override
    public boolean remove(Object o) {
        return delegate.remove(o);
    }

    @Override
    public boolean containsAll(Collection<?> c) {
        return delegate.containsAll(c);
    }

    @Override
    public boolean addAll(Collection<? extends T> c) {
        return delegate.addAll(c);
    }

    @Override
    public boolean removeAll(Collection<?> c) {
        return delegate.removeAll(c);
    }

    @Override
    public boolean retainAll(Collection<?> c) {
        return delegate.retainAll(c);
    }

    @Override
    public void clear() {
        delegate.clear();
    }

    @Override
    public String toString() {
        return "" + delegate.toString();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        QuickCollection that = (QuickCollection) o;

        if (delegate != null ? !delegate.equals(that.delegate) : that.delegate != null) return false;

        return true;
    }

    @Override
    public int hashCode() {
        return delegate != null ? delegate.hashCode() : 0;
    }
}

这是儿童DTO课程

@XmlAccessorType(XmlAccessType.PROPERTY)
@XmlType(name = "BuddyCodes")
@XmlRootElement(name = "BuddyCodes")
public class BuddyCodes extends QuickCollection<String> implements Xml {

    private Long accountId;

    private Date expirationDate;

    public BuddyCodes() {
        super.delegate = new HashSet<String>();
    }

    public BuddyCodes(Long accountId, Set<String> codes, Date expirationDate) {
        super(codes);
        this.accountId = accountId;
        this.expirationDate = expirationDate;
        super.delegate = new HashSet<String>();

    }

    public BuddyCodes(Long accountId, Date expirationDate) {
        this.accountId = accountId;
        this.expirationDate = expirationDate;
        super.delegate = new HashSet<String>();
    }

    @Override
    public String toXml() {
        String retVal;
        try {
            retVal = StringUtils.toXml(this);
        }
        catch (JAXBException e) {
            retVal = e.toString();
        }
        return retVal;

    }

    public Long getAccountId() {
        return accountId;
    }

    public void setAccountId(Long accountId) {
        this.accountId = accountId;
    }

    public Set<String> getCodes() {
        return (Set<String>) super.delegate;
    }

    @XmlElement(name = "code")
    public void setCodes(Set<String> codes) {
        super.delegate = codes;
    }

    public Date getExpirationDate() {
        return expirationDate;
    }

    public void setExpirationDate(Date expirationDate) {
        this.expirationDate = expirationDate;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        BuddyCodes that = (BuddyCodes) o;

        if (accountId != null ? !accountId.equals(that.accountId) : that.accountId != null) return false;
        if (delegate != null ? !super.delegate.equals(that.delegate) : that.delegate != null) return false;
        if (expirationDate != null ? !expirationDate.equals(that.expirationDate) : that.expirationDate != null)
            return false;

        return true;
    }

    @Override
    public int hashCode() {
        int result = accountId != null ? accountId.hashCode() : 0;
        result = 31 * result + (expirationDate != null ? expirationDate.hashCode() : 0);
        result = 31 * result + (super.delegate != null ? super.delegate.hashCode() : 0);
        return result;
    }

    @Override
    public String toString() {
        return "BuddyCodes{" +
                "accountId=" + accountId +
                "codes=" + super.delegate +
                ", expirationDate=" + expirationDate +
                '}';
    }
}

它不起作用.我收到了错误.

现在,这是删除继承后的子类,它的工作原理!

import javax.xml.bind.JAXBException;
import javax.xml.bind.annotation.*;
import java.util.Collection;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;

/**
 * @author christian.bongiorno
 *         Date: 10/3/11
 *         Time: 6:11 PM
 */
@XmlAccessorType(XmlAccessType.PROPERTY)
@XmlType(name = "BuddyCodes")
@XmlRootElement(name = "BuddyCodes")
public class BuddyCodes implements Xml {

    private Long accountId;

    private Date expirationDate;
    private Set<String> delegate;
    public BuddyCodes() {
        delegate = new HashSet<String>();
    }

    public BuddyCodes(Long accountId, Set<String> codes, Date expirationDate) {
        this.accountId = accountId;
        this.expirationDate = expirationDate;
        delegate = new HashSet<String>();

    }

    public BuddyCodes(Long accountId, Date expirationDate) {
        this.accountId = accountId;
        this.expirationDate = expirationDate;
        delegate = new HashSet<String>();
    }

    @Override
    public String toXml() {
        String retVal;
        try {
            retVal = StringUtils.toXml(this);
        }
        catch (JAXBException e) {
            retVal = e.toString();
        }
        return retVal;

    }

    public Long getAccountId() {
        return accountId;
    }

    public void setAccountId(Long accountId) {
        this.accountId = accountId;
    }

    public Set<String> getCodes() {
        return delegate;
    }

    @XmlElement(name = "code")
    public void setCodes(Set<String> codes) {
        delegate = codes;
    }

    public Date getExpirationDate() {
        return expirationDate;
    }

    public void setExpirationDate(Date expirationDate) {
        this.expirationDate = expirationDate;
    }

    public boolean add(String s) {
        return delegate.add(s);
    }

    public int size() {
        return delegate.size();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        BuddyCodes that = (BuddyCodes) o;

        if (accountId != null ? !accountId.equals(that.accountId) : that.accountId != null) return false;
        if (delegate != null ? !delegate.equals(that.delegate) : that.delegate != null) return false;
        if (expirationDate != null ? !expirationDate.equals(that.expirationDate) : that.expirationDate != null)
            return false;

        return true;
    }

    @Override
    public int hashCode() {
        int result = accountId != null ? accountId.hashCode() : 0;
        result = 31 * result + (expirationDate != null ? expirationDate.hashCode() : 0);
        result = 31 * result + (delegate != null ? delegate.hashCode() : 0);
        return result;
    }


}

为什么继承很重要？

我没有想到这一点,但我有一个类似布局的另一个DTO(BuddyTypes BuddyType).BuddyType有2个成员:Long和String.两者都被注释为XmlElement.这个工作得很好.

似乎问题是组成委托的集合成员在我的问题案例中没有注释,我不知道如何注释父成员.作为继承类,使用某种默认名称/注释是没有意义的.但是,我尝试了这种疯狂并且注释被忽略了 - 我之前看到父成员注释被忽略了所以这不是新的.

我不知道是否可能,但我需要注释一个父成员.

Answer 1

有点开箱即用：尝试简单的 XML库而不是 JAXB。我的经验是最好的。