小编pad*_*dis的帖子

我有1-N关系(对象有一个列表),并希望从列表中删除一个项目.使用JPA删除列表中项目的正确方法是什么？

我是否必须首先更新列表并合并所有者并删除项目后(如果我不删除项目并且只是合并所有者,孤立将保留在DB中,对吧？)？在调用merge()和remove()的顺序中,remove()和merge()的顺序是否重要？

代码示例:

List<Item> items = owner.getItems();
Item itemToRemove = items.get(index);
owner.remove(itemToRemove);
em.merge(owner);
em.remove(itemToRemove);

我在Spring Batch中的JobRepository上使用SERIALIZED隔离级别获取此异常:

org.springframework.dao.CannotSerializeTransactionException: PreparedStatementCallback; SQL [INSERT into DATAFEED_APP.BATCH_JOB_INSTANCE(JOB_INSTANCE_ID, JOB_NAME, JOB_KEY, VERSION) values (?, ?, ?, ?)]; ORA-08177: can't serialize access for this transaction

; 嵌套异常是java.sql.SQLException:ORA-08177:无法序列化此事务的访问权限

at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:269)
at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:72)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:603)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:812)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:868)
at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:872)
at org.springframework.batch.core.repository.dao.JdbcJobInstanceDao.createJobInstance(JdbcJobInstanceDao.java:105)
at org.springframework.batch.core.repository.support.SimpleJobRepository.createJobExecution(SimpleJobRepository.java:135)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.batch.core.repository.support.AbstractJobRepositoryFactoryBean$1.invoke(AbstractJobRepositoryFactoryBean.java:172)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy27.createJobExecution(Unknown Source)
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597) …

我正进入(状态

Caused by: java.net.NoRouteToHostException: No route to host
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:529)
at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:564)
at sun.reflect.GeneratedMethodAccessor638.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.commons.httpclient.protocol.ReflectionSocketFactory.createSocket(ReflectionSocketFactory.java:140)
at org.apache.commons.httpclient.protocol.SSLProtocolSocketFactory.createSocket(SSLProtocolSocketFactory.java:130)
at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707)
at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387)
at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323)

贾瓦多克说

表示尝试将套接字连接到远程地址和端口时发生错误.通常,由于中间防火墙或中间路由器关闭,无法访问远程主机.

这是客户端或远程端的错误,还是它们中的任何一个？

我有一份我需要编组的列表地图.我创建了XML适配器,但java.util.List is an interface, and JAXB can't handle interfaces.在创建JAXB上下文时我一直在努力.我该如何编组列表地图？

这是我的代码:

@XmlRootElement(name = "myClass")
public class MyClass  {

    @XmlJavaTypeAdapter(MapOfListsAdapter.class)
    protected Map<Integer, List<Condition>> expectedResults;

我为Map编写了适配器MapOfListsAdapater:

public class MapOfListsAdapter extends XmlAdapter<List<MapOfListsEntry>, Map<Integer, List<Condition>>> {

    @Override
    public List<MapOfListsEntry> marshal(Map<Integer, List<Condition>> v) {...}

    @Override
    public Map<Integer, List<Condition>> unmarshal(List<MapOfListsEntry> v) {...}
}

MapOfListEntry具有以下JAXB注释:

public class MapOfListsEntry {

    @XmlAttribute
    private Integer key;

    @XmlElementRef
    @XmlElementWrapper
    private List<Condition> value;

我正在调用Version One REST API并继续收到XMLHttpRequest cannot load https://www10.v1host.com/... Origin http://localhost:8080 is not allowed by Access-Control-Allow-Origin.javascript错误.我发送GET请求,预计XML内容将作为响应返回.这是我的jQuery代码:

$.ajax({
  dataType: "xml",
  url: "https://www10.v1host.com/...",
  success: function(data, status, xhr) {
  alert("Load was performed.");
  }
});

我已经改变了dataType: "jsonp"并且通过这种方式我得到了这种格式的回应:

jsonp1294354293197(<?xml version="1.0" encoding="UTF-8"?><Asset ...</Asset>)

但是得到另一个javascript错误:" Uncaught SyntaxError: Unexpected token <"

有没有办法如何获取跨域XML休息数据(类似于XMLp)或为jsonp做一个变通方法(防止解析JSON格式并使用我自己的解析XML)？

使用jQuery,我调用的是Version One Rest API,需要在HTTP头中验证用户身份.

我试过了

$.ajax({
        dataType: "jsonp",
        beforeSend: function(xhr){
            xhr.setRequestHeader("Authorization", "Basic xyz"); // xyz usr:pwd Base64 encoded
        },
        url: "https://www10.v1host.com/.../VersionOne/rest-1.v1/...",
        success: function(data, status, xhr) {
            alert("Load was performed.");
        }
    });

和

$.ajax({
    dataType: "jsonp",
    username:"usr",
    password:"pwd",
    url: "https://www10.v1host.com/.../VersionOne/rest-1.v1/...",
    success: function(data, status, xhr) {
        alert("Load was performed.");
    }
});

但我总是弹出来询问我的凭据(我使用Chrome).即使我在弹出窗口中键入凭据,我也没有通过身份验证,窗口仍然显示.

1. 如何在HTTP头中使用jQuery对用户进行身份验证？
2. 是否有任何方法使密码属性加密不可见？或Base64是唯一的方法.我想只通过一个帐户访问服务器,但不希望客户端的用户看到密码(或在javascripts中找到它).

在托管模式下运行我的GWT应用程序(gwt 2.0.4)时,调用在远程Tomcat上运行的RPC方法,我得到GWT序列化异常:

INFO: GwtRpcEventSrvc: ERROR: The serialization policy file '/84EC7BA65AF8175BAA99B47877FDE163.gwt.rpc' was not found; did you forget to include it in this deployment?

SEVERE: GwtRpcEventSrvc: WARNING: Failed to get the SerializationPolicy '84EC7BA65AF8175BAA99B47877FDE163' for module 'http://host:19980/MYAPP/'; a legacy, 1.3.3 compatible, serialization policy will be used.  Youmay experience SerializationExceptions as a result.

SEVERE: Exception while dispatching incoming RPC call
Throwable occurred: com.google.gwt.user.client.rpc.SerializationException: java.lang.reflect.InvocationTargetException
.at com.google.gwt.user.server.rpc.impl.ServerSerializationStreamWriter.serializeWithCustomSerializer(ServerSerializationStreamWriter.java:760)
.at com.google.gwt.user.server.rpc.impl.ServerSerializationStreamWriter.serializeImpl(ServerSerializationStreamWriter.java:723)
.at com.google.gwt.user.server.rpc.impl.ServerSerializationStreamWriter.serialize(ServerSerializationStreamWriter.java:612)
.at com.google.gwt.user.client.rpc.impl.AbstractSerializationStreamWriter.writeObject(AbstractSerializationStreamWriter.java:129)
.at com.google.gwt.user.server.rpc.impl.ServerSerializationStreamWriter$ValueWriter$8.write(ServerSerializationStreamWriter.java:152)
...
Caused by: com.google.gwt.user.client.rpc.SerializationException: Type 'com.mypackage.data.MyData' was not assignable to …

当我部署更新版本的GWT应用程序时,有时会出现此日志错误:

SEVERE: GwtRpcEventSrvc: WARNING: Failed to get the SerializationPolicy 'www.host.com:22041/MYAPP/'; a legacy, 1.3.3 compatible, serialization policy will be 
 a result.                                                                      

• 问题1)浏览器缓存中是否存在序列化策略文件的问题？
• 问题2)如何防止此类日志消息？我尝试将更改的URL请求参数添加到nocache.js(<script src="MyApp.nocache.js?v=123"...)但它没有帮助.

在Eclipse(Helios)中打开JSF页面(JSF + Apache Trinidad + facelet)时,Eclipse会在页面打开前冻结几秒钟.

此外,在编辑页面时,代码完成/语法验证很慢 - 例如我输入<tr:并且我必须等待几秒钟才能继续输入或显示tr标签.

每次输入开始标签时我都要等待并且让我慢慢减速,这是非常烦人的.

我也在使用自定义facelet标签.

怎么做才能避免Eclipse冻结/放慢速度？我是否必须更改任何配置才能加快速度？