172만명의 커뮤니티!! 함께 토론해봐요.
미해결
블록체인 기반의 스마트컨트랙트 개발
우선 그 동안 질문했던거 답변을 너무 잘해주셔서 다 해결을 했습니다!ㅎ 정말 감사합니다. 근데 확실히 익숙하지 않아서 영상보면서 자꾸 하게 되네요. 반복 학습을 해야겠어요. 그리고 혹시 sublime에 있는 코딩 파일들도 올려주실수 있으신가요?? ova에 있는걸로 사용할 수도 있는데 제가 패럴러즈를 이용해서 그런지 ova로 연동이 안되네요ㅠㅠ 부탁드립니다~
해결됨
블록체인 이더리움 부동산 댑(Dapp) 만들기 - 기본편
안녕하세요. 저는 mac으로 사용하고 있는데, geth attach ipc:\.pipegeth.ipc로는 접근이 불가능 한 상태입니다. mac에 맞는 다른 명령어를 안내 받을 수 있나요??
미해결
JSP 강의평가 웹 사이트 개발하기
Loading class com.mysql.jdbc.Driver'. This is deprecated. The new driver class is com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary. Thu Jun 14 00:00:33 KST 2018 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification. java.sql.SQLException: The server time zone value '´???¹?±¹ ???ؽ?' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:127) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:95) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:87) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:61) at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:71) at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:862) at com.mysql.cj.jdbc.ConnectionImpl.(ConnectionImpl.java:444) at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:230) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:226) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) at util.DatabaseUtil.getConnection(DatabaseUtil.java:14) at user.UserDAO.join(UserDAO.java:14) at org.apache.jsp.userJoinAction_jsp._jspService(userJoinAction_jsp.java:139) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source) Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value '´???¹?±¹ ???ؽ?' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:59) at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:83) at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:128) at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2201) at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2225) at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1391) at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:993) at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:852) ... 36 more java.lang.NullPointerException at user.UserDAO.join(UserDAO.java:15) at org.apache.jsp.userJoinAction_jsp._jspService(userJoinAction_jsp.java:139) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330) at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source)
미해결
누구나 따라하면서 배우는 JSP 커뮤니티 게시판 만들기
String dbURL = "jdbc:mysql://localhost:3306/BBS?serverTimezone=UTC"; Class.forName("com.mysql.cj.jdbc.Driver"); 저는 계속해서 -2에 걸려 데이터 베이스 오류가 났습니다. MySQL 은 8.~버전을 이용중이고 이제는 com.mysql.jdbc.Driver 에서 com.mysql.cj.jdbc.Driver 로 바뀌었고 Time Zone 때문에 구글링 해봤더니 String dbURL = "jdbc:mysql://localhost:3306/BBS?serverTimezone=UTC"; 하라고 나옵니다. 저와 같은 증상이신 분에게 도움이 됬으면 합니다.
미해결
신입 프로그래머를 위한 실전 JSP 강좌
response.setContentType("text/html; charset=EUC-KR"); PrintWriter writer = response.getWriter(); writer.print(""); writer.print(""); writer.print(""); writer.print(""); writer.print("Post방식입니다. 따라서 doPost메소드가 호출 되었습니다"); writer.print(""); writer.print(""); 분명 보기와 똑같이 쳣는데도 한글만 깨져요.. 실행 결과가 Post?????. ??? doPost???? ?? ????? 이렇게 나옵니다.. 그리구 실행결과 항상 첫줄에 Served at: /hbk0514 이렇게 나오는데 이건 왜 나오는거죠..? 동영상 강의보면 두겟 메소드 아래 안보이는 소스가 재 이클립스 상에서는 존재합니다. response.getWriter().append("Served at: ").append(request.getContextPath()); 위에 소스코드는 신경 안써두 되나요...?
