可能重复:
用Java表示货币价值
哪种java类型处理价格值好？请告诉我为什么？
我不知道这只是问题:)
我只知道这种类型必须"安全".因为如果我们创建商店应用或者那样的想法.
PS.我需要最好的实践
以及它在数据库中的表现方式？
你好,当我尝试在glassfish中部署耳朵app时,我有很多警告:
[#|2013-01-14T14:12:52.404+0100|WARNING|glassfish3.1.2|org.apache.jasper.runtime.TldScanner|_ThreadID=34;_ThreadName=Thread-2;|PWC6351: In TLD scanning, the supplied resource file:/usr/local/glassfish3/glassfish/domains/pi/applications/person-ear-1.0-SNAPSHOT-rnull/APP-INF/lib/jaxb-api-2.1.jar does not exist
java.io.FileNotFoundException: /usr/local/glassfish3/glassfish/domains/pi/applications/person-ear-1.0-SNAPSHOT-rnull/APP-INF/lib/jaxb-api-2.1.jar (Nie ma takiego pliku ani katalogu)
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:214)
at java.util.zip.ZipFile.<init>(ZipFile.java:144)
at java.util.jar.JarFile.<init>(JarFile.java:152)
at java.util.jar.JarFile.<init>(JarFile.java:89)
[#|2013-01-14T14:12:52.407+0100|WARNING|glassfish3.1.2|org.apache.jasper.runtime.TldScanner|_ThreadID=34;_ThreadName=Thread-2;|PWC6351: In TLD scanning, the supplied resource file:/usr/local/glassfish3/glassfish/domains/pi/applications/person-ear-1.0-SNAPSHOT-rnull/APP-INF/lib/resolver-20050927.jar does not exist
java.io.FileNotFoundException: /usr/local/glassfish3/glassfish/domains/pi/applications/person-ear-1.0-SNAPSHOT-rnull/APP-INF/lib/resolver-20050927.jar (Nie ma takiego pliku ani katalogu)
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:214)
at java.util.zip.ZipFile.<init>(ZipFile.java:144)
at java.util.jar.JarFile.<init>(JarFile.java:152
其他....对我而言,玻璃鱼不使用他自己的类加载器,但我不确定....
我有,Observable<Rates>而Rate只是一个简单的对象:
Rate(val value:String){}
Rates(val rates: List<Rate>)
我想改变Observable<Rates>成Observable<HashMap<String,Long>.
所以例如对于Rates(arrayOf(Rate("1"),Rate("2"), Rate("3"),Rate("3"), Rate("2"),Rate("2")))我期望结果的费率:
(1 -> 1)
(2 -> 3)
(3 -> 2)
(4 -> 0)
(5 -> 0)
我开始创建类似的东西:
service.getRates()
.flatMap {it-> Observable.from(it.rates) }
.filter { !it.value.isNullOrEmpty() }
.groupBy {it -> it.value}
.collect({ HashMap<String,Long>()}, { b, t -> b.put(t.key, t.count???)}
但我被困在这里,我不知道所有的价值？如果没有5中的4,我不知道如何添加空值(0).有没有办法用rx做到这一点？
测试android主屏幕小部件的最佳方法是什么？很难找到任何示例代码:/哪些框架支持测试？
根据这个答案，线程局部变量当我们使用线程局部时，我们应该清除线程池环境中的所有变量。
因此，基本上我只想确认一下，当我们使用MDC（映射诊断上下文）时，我们还应该清除MDC以意识到内存泄漏，这是真的吗？
例如：
public class HttpInterceptor implements HandlerInterceptor
{
@Override
public boolean preHandle(HttpServletRequest request,HttpServletResponse response, final Object handler){
....
MDC.put(SESSION_ID, session_id);
{
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, final Object handler,
final ModelAndView modelAndView)
{
MDC.clear(); //WE SHOULD CLEAR MDC.... if not memory leaks ?
}
}
我知道为什么我的依赖不起作用.这是我的配置:
ext {
junitVersion = "4.11"
libs = [
junit : dependencies.create("junit:junit:4.11")
]
}
configure(subprojects) { subproject ->
dependencies {
testCompile(libs.junit)
}
}
我有错误:
* What went wrong:
A problem occurred evaluating root project 'unit590'.
> Could not find method testCompile() for arguments [DefaultExternalModuleDependency{group='junit', name='junit', version='4.11', configuration='default'}] on org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler_Decorated@785c1069.
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
谢谢你的帮助
我知道有很多问题,但我无法找到解决问题的好方法.
我使用Jboss作为7,Spring和Hibernate(4)作为JPA 2.0提供程序,所以我有简单的@OneToMany双向关系:
我有这样的超级人:
@MappedSuperclass
@Inheritance(strategy=InheritanceType.JOINED)
public abstract class Person {
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
private Long id;
@NotNull
@Size(min = 1, max = 25)
@Pattern(regexp = "[A-Za-z ]*", message = "must contain only letters and spaces")
private String name;
public Person(String name) {
super();
this.name = name;
}
和班级成员:
@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = "email"))
public class Member extends Person implements Serializable
{
/** Default value included to remove warning. Remove or modify at will. **/
private static final long serialVersionUID …我不知道是否可以将数组反序列化为我拥有json的hashMap：
"additionalProperties": [
{
"$type": "Tfl.Api.Presentation.Entities.AdditionalProperties, Tfl.Api.Presentation.Entities",
"category": "Description",
"key": "TerminalName",
"sourceSystemKey": "BikePoints",
"value": "200017",
"modified": "2016-05-19T12:02:39.82"
}
........
]
对于这个json我有list：
private List<AdditionalProperties> additionalProperties;
一切正常，但是如何将json存储在HashMap中，其中Key为“ key”（TerminalName）”
private HashMap<String,AdditionalProperties> additionalProperties;
可能重复:
通过Java中的反射访问私有继承的字段
你好我hava用java反射的init值有问题.
我有简单的课程
public class A extends B {
private String name;
}
public class B {
private String superName;
}
而且我也有简单的功能:
public void createRandom(Class<T> clazz , List<String> classFields){
try {
T object = clazz.newInstance();
for(String s : classFields){
clazz.getDeclaredField(s);
}
} catch(Exception e){
}
}
我的功能做其他的东西,但我有问题,因为我有错误:
java.lang.NoSuchFieldException: superName
如何使用反射从超类设置所有类字段也字段？
我有所有类字段(也继承),我正在使用函数,field.set(Object obj, Object value)但这样我不能设置继承的类字段:/
我没有问题得到所有类字段我使用Spring ReflectionUtils.doWithfield.我存储了所有字段名称List<String> classField,所以我知道所有clazz字段也都继承了.但我的问题是如何将值设置为所有clazz字段.
你好我在我的本地机器openfireserver安装.
下面是我的http绑定配置:![Openfire配置http-config] [1]
我还在Pidgin中添加了新用户:
高级:
http://localhost/http-bind/但连接失败了.
如果我尝试使用此选项:
http://localhost:7070/http-bind/我在openfire中遇到了另一个错误:
2013.03.15 20:50:15 org.eclipse.jetty.servlet.ServletHandler - /http-bind/
java.util.concurrent.RejectedExecutionException: Task org.jivesoftware.openfire.http.HttpSessionManager$HttpPacketSender@65e92309 rejected from java.util.concurrent.ThreadPoolExecutor@18ee24bf[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 0]
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2048)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:821)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1372)
at org.jivesoftware.openfire.http.HttpSessionManager$HttpPacketSender.init(HttpSessionManager.java:417)
at org.jivesoftware.openfire.http.HttpSessionManager$HttpPacketSender.access$200(HttpSessionManager.java:405)
at org.jivesoftware.openfire.http.HttpSessionManager.forwardRequest(HttpSessionManager.java:319)
at org.jivesoftware.openfire.http.HttpBindServlet.handleSessionRequest(HttpBindServlet.java:254)
at org.jivesoftware.openfire.http.HttpBindServlet.parseDocument(HttpBindServlet.java:176)
at org.jivesoftware.openfire.http.HttpBindServlet.doPost(HttpBindServlet.java:145)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:547)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:480)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:225)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:941)
at …您好我有这样的功能:
@Override
public boolean checkExist(String name) {
final boolean check[] = new boolean[] { false };
getAllRecordFromServer(new SearchCallback() {
@Override
public void onSearchResult(Map<String, Item> itemsMap) {
//do some action set true when map key equals name
check[0] = true;
}
@Override
public void onSearchError(XMLPacket error) {
// TODO Auto-generated method stub
}
});
return check[0];
}
我正在寻找解决方案并找到一些文章,但我不知道如何在gwt中执行:/此代码无法正常工作...因为您知道这是异步回调.
我怎样才能解决这个问题,我必须在回调结束后返回值.
您好我使用exec命令编写了简单的java函数.此函数检查系统(linux)中是否存在该字体.首先我写了简单的bash命令:identify -list font | grep -i 'Font: Times-Bold' -w它的工作完美,所以我创建了简单的程序:
public abstract class SystemReader{
public static final void checkFontExist(String name){
String command = "identify -list font | grep -i -w \'Font: " + name + "\'";
Process p =Runtime.getRuntime().exec(command);
String lines = "";
String resoults ="";
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(p.getInputStream()));
while((line buferedReader.readLine())!=null){
resoult += line + "\n";
}
System.out.println("RESPONSE: " + resoult);
bufferreader.close();
}
}
它的工作但不是我的意思.此函数返回我系统中存在的所有字体.它似乎命令grep不是exec？
我尝试使用另一个版本的命令exec()我创建:
String command = {"identify -list font", "grep -i …我是PostgreSQL的新手,我在将数据库从Oracle迁移到PostgreSQL 9.2时遇到了问题.我必须在我的代码中更改一些本机查询.我有一个子查询,如:
SELECT wm_concat(p.first_name || ' ' || p.last_name)
FROM TODO_PERSON PR
JOIN PERSON P ON (p.id == pr.person_id)
WHERE todo_id = internal_table.id
在PostgreSQL中我找不到等效的功能或其他解决方案......