我有一个控制器，POST处理程序定义如下：
@RequestMapping(value="/ajax/saveVendor.do",method = RequestMethod.POST) public @ResponseBody AjaxResponse saveVendor( @Valid UIVendor vendor,BindingResult result,Locale currentLocale )
当以JSON格式查看时，UIVendor对象如下所示：
var vendor =
{
vendorId: 123,vendorName: "ABC Company",emails : [
{ emailAddress: "abc123@abc.com",flags: 2 },{ emailAddress: "xyz@abc.com",flags: 3 }
]
}
UIVendor bean有一个名为“Emails”的字段，类型为ArrayList，带有适当的setter和getter(getEmails / setEmails)。 NotificationEmail对象也具有适当的公共setter / getter。
当我尝试使用以下代码发布对象时：
$.post("ajax/saveVendor.do",$.param(vendor),saveEntityCallback,"json" );
我在日志中收到此错误：
Invalid property 'emails[0][emailAddress]' of bean class [beans.UIVendor]: Property referenced in indexed property path 'emails[0][emailAddress]' is neither an array nor a List nor a Map; returned value was [abc123@abc.com]
如何正确地将这样的嵌套对象发布到Spring控制器并将其正确地反序列化到适当的对象结构中。
UPDATE
根据Per Bohzo的要求，这里是UIVendor类的内容。此类包装Web服务生成的bean类，将VendorAttributes作为单独的字段公开：
package com.mycompany.beans;
import java.util.*;
import org.apache.commons.lang.*;
import com.mycompany.domain.Vendor;
import com.mycompany.domain.VendorAttributes;
import org.apache.commons.logging.*;
import org.codehaus.jackson.annotate.JsonIgnore;
public class UIVendor
{
private final Log logger = LogFactory.getLog( this.getClass() );
private Vendor vendor;
private boolean ftpFlag;
private String ftpHost;
private String ftpPath;
private String ftpUser;
private String ftpPassword;
private List<UINotificationEmail> emails = null;
public UIVendor() { this( new Vendor() ); }
public UIVendor( Vendor vendor )
{
this.vendor = vendor;
loadVendorAttributes();
}
private void loadVendorAttributes()
{
this.ftpFlag = false;
this.ftpHost = this.ftpPassword = this.ftpPath = this.ftpUser = "";
this.emails = null;
for ( VendorAttributes a : this.vendor.getVendorAttributes() )
{
String key = a.getVendorFakey();
String value = a.getVendorFaValue();
int flags = a.getFlags();
if ( StringUtils.isBlank(key) || StringUtils.isBlank(value) ) continue;
if ( key.equals( "ftpFlag" ) )
{
this.ftpFlag = BooleanUtils.toBoolean( value );
}
else if ( key.equals( "ftpHost" ) )
{
this.ftpHost = value;
}
else if ( key.equals("ftpPath") )
{
this.ftpPath = value;
}
else if ( key.equals("ftpUser") )
{
this.ftpUser = value;
}
else if ( key.equals("ftpPassword") )
{
this.ftpPassword = value;
}
else if ( key.equals("email") )
{
UINotificationEmail email = new UINotificationEmail(value,flags);
this.getEmails().add( email );
}
}
}
private void saveVendorAttributes()
{
int id = this.vendor.getVendorId();
List<VendorAttributes> attrs = this.vendor.getVendorAttributes();
attrs.clear();
if ( this.ftpFlag )
{
VendorAttributes flag = new VendorAttributes();
flag.setVendorId( id );
flag.setStatus( "A" );
flag.setVendorFakey( "ftpFlag" );
flag.setVendorFaValue( BooleanUtils.toStringTrueFalse( this.ftpFlag ) );
attrs.add( flag );
if ( StringUtils.isNotBlank( this.ftpHost ) )
{
VendorAttributes host = new VendorAttributes();
host.setVendorId( id );
host.setStatus( "A" );
host.setVendorFakey( "ftpHost" );
host.setVendorFaValue( this.ftpHost );
attrs.add( host );
if ( StringUtils.isNotBlank( this.ftpPath ) )
{
VendorAttributes path = new VendorAttributes();
path.setVendorId( id );
path.setStatus( "A" );
path.setVendorFakey( "ftpPath" );
path.setVendorFaValue( this.ftpPath );
attrs.add( path );
}
if ( StringUtils.isNotBlank( this.ftpUser ) )
{
VendorAttributes user = new VendorAttributes();
user.setVendorId( id );
user.setStatus( "A" );
user.setVendorFakey( "ftpUser" );
user.setVendorFaValue( this.ftpUser );
attrs.add( user );
}
if ( StringUtils.isNotBlank( this.ftpPassword ) )
{
VendorAttributes password = new VendorAttributes();
password.setVendorId( id );
password.setStatus( "A" );
password.setVendorFakey( "ftpPassword" );
password.setVendorFaValue( this.ftpPassword );
attrs.add( password );
}
}
}
for ( UINotificationEmail e : this.getEmails() )
{
logger.debug("Adding email " + e );
VendorAttributes email = new VendorAttributes();
email.setStatus( "A" );
email.setVendorFakey( "email" );
email.setVendorFaValue( e.getEmailAddress() );
email.setFlags( e.getFlags() );
email.setVendorId( id );
attrs.add( email );
}
}
@JsonIgnore
public Vendor getVendor()
{
saveVendorAttributes();
return this.vendor;
}
public int getVendorId()
{
return this.vendor.getVendorId();
}
public void setVendorId( int vendorId )
{
this.vendor.setVendorId( vendorId );
}
public String getVendorType()
{
return this.vendor.getVendorType();
}
public void setVendorType( String vendorType )
{
this.vendor.setVendorType( vendorType );
}
public String getVendorName()
{
return this.vendor.getVendorName();
}
public void setVendorName( String vendorName )
{
this.vendor.setVendorName( vendorName );
}
public String getStatus()
{
return this.vendor.getStatus();
}
public void setStatus( String status )
{
this.vendor.setStatus( status );
}
public boolean isFtpFlag()
{
return this.ftpFlag;
}
public void setFtpFlag( boolean ftpFlag )
{
this.ftpFlag = ftpFlag;
}
public String getFtpHost()
{
return this.ftpHost;
}
public void setFtpHost( String ftpHost )
{
this.ftpHost = ftpHost;
}
public String getFtpPath()
{
return this.ftpPath;
}
public void setFtpPath( String ftpPath )
{
this.ftpPath = ftpPath;
}
public String getFtpUser()
{
return this.ftpUser;
}
public void setFtpUser( String ftpUser )
{
this.ftpUser = ftpUser;
}
public String getFtpPassword()
{
return this.ftpPassword;
}
public void setFtpPassword( String ftpPassword )
{
this.ftpPassword = ftpPassword;
}
public List<UINotificationEmail> getEmails()
{
if ( this.emails == null )
{
this.emails = new ArrayList<UINotificationEmail>();
}
return emails;
}
public void setEmails(List<UINotificationEmail> emails)
{
this.emails = emails;
}
}
更新2
这是杰克逊的输出：
{
"vendorName":"MAIL","vendorId":45,"emails":
[
{
"emailAddress":"dfg","success":false,"failure":false,"flags":0
}
],"vendorType":"DFG","ftpFlag":true,"ftpHost":"kdsfjng","ftpPath":"dsfg","ftpUser":"sdfg","ftpPassword":"sdfg","status":"A"
}
这是我在POST上返回的对象的结构：
{
"vendorId":"45","vendorName":"MAIL","status":"A","emails":
[
{
"success":"false","failure":"false","emailAddress":"dfg"
},{
"success":"true","failure":"true","emailAddress":"pfc@sj.org"
}
]
}
我也尝试过使用www.json.org上的JSON库进行序列化，结果就是你在上面看到的。但是，当我发布该数据时，传递给控制器的UIVendor对象中的所有字段都为空(尽管该对象不是)。
解决方法
更新：从Spring 3.1开始，可以使用
@Valid On @RequestBody Controller Method Arguments。
@RequestMapping(value="/ajax/saveVendor.do",method = RequestMethod.POST) public @ResponseBody AjaxResponse saveVendor( @Valid @RequestBody UIVendor vendor,Locale currentLocale )
经过多次反复试验，我终于想出了问题所在。使用以下控制器方法签名时：
@RequestMapping(value="/ajax/saveVendor.do",Locale currentLocale )
客户端脚本必须以后数据(通常是“application / x-www-form-urlencoded”)格式传递对象中的字段(即，field = value& field2 = value2)。这是在jQuery中完成的，如下所示：
$.post( "mycontroller.do",$.param(object),callback,"json" )
这适用于没有子对象或集合的简单POJO对象，但是一旦为传递的对象引入了显着的复杂性，jQuery用于序列化对象数据的符号就不会被Spring的映射逻辑识别：
object[0][field]
@RequestMapping(value="/ajax/saveVendor.do",method = RequestMethod.POST) public @ResponseBody AjaxResponse saveVendor( @RequestBody UIVendor vendor,Locale currentLocale )
并将呼叫从客户端更改为：
$.ajax(
{
url:"ajax/mycontroller.do",type: "POST",data: JSON.stringify( objecdt ),success: callback,dataType: "json",contentType: "application/json"
} );
这需要使用JSON javascript库。它还强制将contentType设置为“application / json”，这是Spring在使用@RequestBody注释时所期望的，并将对象序列化为Jackson可以反序列化为有效对象结构的格式。
唯一的副作用是现在我必须在控制器方法中处理我自己的对象验证，但这相对简单：
BindingResult result = new BeanPropertyBindingResult( object,"MyObject" ); Validator validator = new MyObjectValidator(); validator.validate( object,result );
如果有人有任何改进这个过程的建议，我会全力以赴。
