我正在開發一個GWT Web應用程序,並試圖從我的RemoteServiceServlet實現(對於rpc)連接到一個mysql數據庫。Java/GWT/MySQL:連接拒絕?
服務器運行,我可以從我工作的機器連接到數據庫。出於測試目的,我編寫了一個只連接到數據庫的小程序。這工作:
Class.forName("com.mysql.jdbc.Driver");
Connection connection = DriverManager.getConnection("jdbc:mysql://192.168.0.106:3306/dbname", "dbuser", "dbpasswd");
但同樣的線路在我的GWT應用程序失敗,約100堆棧跟蹤的行,這裏是「事業」:
Caused by: java.net.SocketException: java.security.AccessControlException: access denied (java.net.SocketPermission 192.168.0.106:3306 connect,resolve)
at com.mysql.jdbc.StandardSocketFactory.unwrapExceptionToProperClassAndThrowIt(StandardSocketFactory.java:408)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:269)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:294)
... 55 more
,現在我的問題:爲什麼?
編輯:測試我使用的開發模式,鉻和GWT插件
EDIT2:代碼的一部分它崩潰了:
public DataLinkImpl() {
Connection tmpConnection = null;
try {
Class.forName("com.mysql.jdbc.Driver");
tmpConnection = DriverManager.getConnection("jdbc:mysql://192.168.0.106:3306/dbname", "dbuser", "dbpasswd");
} catch (ClassNotFoundException e) {
System.err.println("jdbc driver class not found");
} catch (SQLException e) {
System.err.println("could not establish database connection");
e.printStackTrace();
e.getNextException().printStackTrace();
} finally {
connection = tmpConnection;
}
}
與以下堆棧跟蹤:
could not establish database connection
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:112)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:120)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2333)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2370)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2154)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:792)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:112)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:120)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:381)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at de.eikecochu.gwt.awidb.server.DataLinkImpl.<init>(DataLinkImpl.java:23)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153)
at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:428)
at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:78)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:362)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: java.net.SocketException: java.security.AccessControlException: access denied (java.net.SocketPermission 192.168.0.106:3306 connect,resolve)
at com.mysql.jdbc.StandardSocketFactory.unwrapExceptionToProperClassAndThrowIt(StandardSocketFactory.java:408)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:269)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:294)
... 55 more
01.12.2011 02:33:09 com.google.appengine.tools.development.ApiProxyLocalImpl log
SCHWERWIEGEND: javax.servlet.ServletContext log: unavailable
java.lang.NullPointerException
at de.eikecochu.gwt.awidb.server.DataLinkImpl.<init>(DataLinkImpl.java:29)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153)
at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:428)
at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:78)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:362)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
01.12.2011 02:33:09 com.google.apphosting.utils.jetty.JettyLogger warn
WARNUNG: /awidb/datalink
java.lang.NullPointerException
at de.eikecochu.gwt.awidb.server.DataLinkImpl.<init>(DataLinkImpl.java:29)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153)
at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:428)
at org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java:339)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:78)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:362)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
edit3:我向我的/Library/Java/.../security/java.policy文件添加了許可:
grant {
permission java.net.SocketPermission "192.168.0.106:3306", "connect,resolve";
}
但仍然一樣,我無法連接到數據庫。我也試圖直接在數據庫所在的機器上執行它,所以我將它部署在tomcat中(在那裏添加了相同的許可),但仍然沒有。 WTF?
edit4:證實了這一點,我寫了一個非常簡單的Web應用程序:
入口點類:
package de.eikecochu.gwt.gwttest.client;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
public class GWTTest implements EntryPoint {
private TestServiceAsync testservice = GWT.create(TestService.class);
@Override
public void onModuleLoad() {
Button b = new Button("test");
RootPanel.get("container").add(b);
b.addClickHandler(new ClickHandler() {
@Override
public void onClick(ClickEvent event) {
testservice.echo("test", new AsyncCallback<String>() {
@Override
public void onFailure(Throwable caught) {
RootPanel.get("container").add(new Label("error"));
}
@Override
public void onSuccess(String result) {
RootPanel.get("container").add(new Label(result));
}
});
}
});
}
}
遠程服務接口:
package de.eikecochu.gwt.gwttest.client;
import com.google.gwt.user.client.rpc.RemoteService;
import com.google.gwt.user.client.rpc.RemoteServiceRelativePath;
@RemoteServiceRelativePath("testservice")
public interface TestService extends RemoteService {
String echo(String s);
}
遠程服務異步接口:
package de.eikecochu.gwt.gwttest.client;
import com.google.gwt.user.client.rpc.AsyncCallback;
public interface TestServiceAsync {
void echo(String s, AsyncCallback<String> callback);
}
RemoteServiceServlet實現:
package de.eikecochu.gwt.gwttest.server;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import de.eikecochu.gwt.gwttest.client.TestService;
public class TestServiceImpl extends RemoteServiceServlet implements
TestService {
private static final long serialVersionUID = 1L;
private final Connection connect() {
String driver = "com.mysql.jdbc.Driver";
String dblink = "jdbc:mysql://192.168.0.106:3306/";
String dbname = "dbname";
String dbuser = "dbuser";
String dbpass = "dbpass";
try {
Class.forName(driver).newInstance();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
Connection conn = null;
try {
conn = DriverManager.getConnection(dblink + dbname, dbuser, dbpass);
} catch (SQLException e) {
System.err.println("mysql connection error: ");
e.printStackTrace();
}
return conn;
}
@Override
public String echo(String s) {
Connection c = connect();
return s;
}
}
這也不起作用。不在我的機器上,也不在本地主機上(數據庫所在的地方)。同樣的錯誤再次出現(AccessControlException bla bla)。
edit5:我試圖直接在我的服務器上執行我的應用程序,這意味着:我在服務器上安裝了eclipse和gwt工具,並在chrome/development模式下在本地執行它。還是一樣的錯誤。我感覺我的mysql/ubuntu有錯誤的配置,或者我從根本上做錯了什麼。通常情況下,連接到數據庫應該很容易,是的?我的意思是,沒有數據庫的網站是什麼...
edit6:正如巴巴建議,我試圖設置 System.setSecurityManager(null);
在我的RemoteServlet連接到數據庫之前。它拋出以下錯誤(略):
java.security.AccessControlException: access denied (java.lang.RuntimePermission setSecurityManager)
at java.security.AccessControlContext.checkPermission(AccessControlContext.java:374)
at java.security.AccessController.checkPermission(AccessController.java:546)
at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
at com.google.appengine.tools.development.DevAppServerFactory$CustomSecurityManager.checkPermission(DevAppServerFactory.java:252)
at java.lang.System.setSecurityManager0(System.java:273)
at java.lang.System.setSecurityManager(System.java:264)
這樣看來我已經安裝了安全管理器。
此外,我試圖用telnet訪問我的數據庫。起初,我的連接被拒絕,但我改變了我的mysql-綁定地址到我的服務器(192.168.0.106)的IP和這裏遵循的步驟:http://ubuntu-commands.blogspot.com/2008/11/how-do-i-enable-remote-access-to-mysql.html
當我telnet 192.168.0.106 3306
現在,奇怪的符號出現:
eikes-macbook-air:~ eike$ telnet 192.168.0.106 3306
Trying 192.168.0.106...
Connected to eike-server.speedport.ip.
Escape character is '^]'.
=
5.1.58-1ubuntu1(b5|529h~!dYpI\rHP:qKc
ot packets out of orderConnection closed by foreign host.
看來這是一個錯誤?
另外,我搜索的存取遭拒錯誤,並發現此鏈接:http://code.google.com/p/gwt-examples/wiki/project_MySQLConn#Tomcat_Setup_Notes 它精確地描述了我遇到的錯誤,雖然我用DEVMODE發展。雖然以下這些步驟沒有幫助(我編輯了我的默認/Library/.../security/java.policy文件)
edit7:我安裝了postgresql,並設置了一個非常簡單的數據庫來測試連接。沒有GWT它工作正常,GWT再次產生相同的錯誤。因此,這不是我的mysql配置的錯誤。我玩了一下java策略文件,沒有任何反應。 GWT恨我:<
edit8:我都嘗試PostgreSQL和MySQL另一臺機器上(此時WIN7)和(編輯策略文件後&之前)執行我的GWT應用程序有本地,還是同樣的錯誤。這是明白無誤的GWT故障!這似乎是不允許在任何地方做gwt devmode ...
另一個問題:錯誤明確指出「java.security.AccessControlException:訪問被拒絕(java.net.SocketPermission localhost resolve)」,那麼爲什麼當我修改我的java策略文件進行連接時,這仍然出現嗎?解決所需的端口?這似乎是完全沒有影響!我甚至嘗試授予AllPermission,也沒有效果。
接下來,我發現「GWT-log.txt的」,其中列出了在裝載過程中出現錯誤:
Public resources found in...
[WARN] Error processing classpath URL 'file:/C:/Program Files (x86)/eclipse/plugin/com.google.gdt.eclipse.designer.hosted.2_2_2.4.2.r37x201110201837/gwt-dev-designtime.jar'
java.net.URISyntaxException: Illegal character in path at index 16: file:/C:/Program Files (x86)/eclipse/plugins/com.google.gdt.eclipse.designer.hosted.2_2_2.4.2.r37x201110201837/gwt-dev-designtime.jar
at java.net.URI$Parser.fail(Unknown Source)
我不知道那是什麼,或者如果它很重要,但它不是我的故障!
您使用的是什麼應用程序服務器? –
你的意思是開發模式?我不使用專用服務器 –
你可以發佈完整的堆棧跟蹤嗎? –