包含java63的词条

E安全 • 2024年3月27日 02:28:21 • Java • 阅读 53

java 类是公共的，应在名为.java 的文件中声明

1、首先在电脑中打开新建的Java项目，新建一个package，在包中新建一个Java 类，如下图所示。

2、定义抽象类User，包含了属性name、age；抽象方法write()。

3、再创建一个子类Pstu，继承父类User，然后重写这些方法。

4、最后在main主方法中，调用子类Pstu，然后依次调用方法write和drink，查看打印结果，如下图所示就就完成了。

java web项目，当数据63条的时候页面可以正常显示和操作，但是数据翻倍的话页面显示非常慢，操作非常卡

显示慢可以优化后台查询的sql

操作慢，没什么好办法浏览器解析页面需要占用电脑内存 cpu是看客户端电脑配置的

image类型怎么初始化java

ava image类初始化

java image类初始化,无法初始化类javax.imageio.ImageIO

科普君冷知识

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我试图将一个

spring web应用程序部署到运行在

windows azure上的生产环境中的tomcat 7(尝试过ubuntu和windows datacenter vm).

遗憾的是,我在生成与

ImageIo一起使用的缩略图时检索到错误(下面的堆栈跟踪).

在开发过程中,我也使用了tomcat 7,所以我真的不明白,生产网络服务器有什么不同.

当我尝试通过“ImageIO.scanForPlugins();”加载模块时exakt同样的事情发生了.是不是ImageIO或javax.awt通常包含在标准的java7 jre中？

我想在META-INF / services / javax.io中设置一个子文件夹或者在堆模式下运行jvm,但没有解决下面的问题.我想我现在真的走在墙上,因为我不知道如何解决这个问题.在本地开发环境(Windows 8,Java7 64B,Tomcat7)上,我没有对上面的这些提示做任何事情(堆模式或类文件),并且一切都运行完美.有这样的事情,应用程序是在没有GPU或类似的服务器上运行的吗？

感谢您提前回复=)

HTTP Status 500 – Handler processing failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class javax.imageio.ImageIOException report

Handler processing failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class javax.imageio.ImageIO

org.springframework.web.util.NestedServletException: Handler processing failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class javax.imageio.ImageIO

org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:972)

org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)

org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)

org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789)

javax.servlet.http.HttpServlet.service(HttpServlet.java:646)

javax.servlet.http.HttpServlet.service(HttpServlet.java:727)

org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)

org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)

org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:118)

org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:84)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:103)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:183)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)

org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:342)

org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:192)

org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:160)

org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)

org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)

java.lang.NoClassDefFoundError: Could not initialize class javax.imageio.ImageIO

ch.yooapps.resman.service.data.FileServiceImpl.createFile(FileServiceImpl.java:63)

sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

java.lang.reflect.Method.invoke(Method.java:606)

org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:319)

org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)

org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)

org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)

org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)

org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)

com.sun.proxy.$Proxy171.createFile(Unknown Source)

ch.yooapps.resman.application.controllers.rest.FileController.attacheFile(FileController.java:61)

sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

java.lang.reflect.Method.invoke(Method.java:606)

org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:213)

org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126)

org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)

org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)

org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)

org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)

org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)