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我正在尝试从本地 AppEngine 服务器中托管的 servlet 连接到 Google Cloud SQL 数据库。当项目部署在 Google 应用引擎上但不是来自本地主机应用引擎服务器时,我能够连接。我收到以下错误消息。
HTTP ERROR 500
Problem accessing /. Reason:
java.lang.IllegalAccessError: com/google/appengine/repackaged/com/google/common/base/Platform
Caused by:
java.sql.SQLException: java.lang.IllegalAccessError: com/google/appengine/repackaged/com/google/common/base/Platform
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:877)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:873)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:443)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)
at java.sql.DriverManager.getConnection(DriverManager.java:571)
at java.sql.DriverManager.getConnection(DriverManager.java:233)
at com.example.appengine.cloudsql.CloudSqlServlet.doGet(CloudSqlServlet.java:88)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:134)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:48)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116)
at org.mortbay.jetty.servlet.ServletHandler$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:95)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:508)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
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.lang.IllegalAccessError: com/google/appengine/repackaged/com/google/common/base/Platform
at com.google.appengine.repackaged.com.google.common.base.Ticker$1.read(Ticker.java:69)
at com.google.appengine.repackaged.com.google.common.base.Stopwatch.elapsedNanos(Stopwatch.java:178)
at com.google.appengine.repackaged.com.google.common.base.Stopwatch.elapsed(Stopwatch.java:191)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LoadingValueReference.elapsedNanos(LocalCache.java:3665)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.getAndRecordStats(LocalCache.java:2382)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2337)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2295)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2208)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache.get(LocalCache.java:4062)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:4066)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4995)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:5001)
at com.google.appengine.api.appidentity.AppIdentityServiceImpl.getAccessToken(AppIdentityServiceImpl.java:272)
at com.google.api.client.googleapis.extensions.appengine.auth.oauth2.AppIdentityCredential.intercept(AppIdentityCredential.java:98)
at com.google.api.client.googleapis.extensions.appengine.auth.oauth2.AppIdentityCredential$AppEngineCredentialWrapper.intercept(AppIdentityCredential.java:243)
at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:859)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:410)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:343)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:460)
at com.google.cloud.sql.mysql.SslSocketFactory.obtainInstanceMetadata(SslSocketFactory.java:370)
at com.google.cloud.sql.mysql.SslSocketFactory.fetchInstanceSslInfo(SslSocketFactory.java:282)
at com.google.cloud.sql.mysql.SslSocketFactory.getInstanceSslInfo(SslSocketFactory.java:262)
at com.google.cloud.sql.mysql.SslSocketFactory.createAndConfigureSocket(SslSocketFactory.java:181)
at com.google.cloud.sql.mysql.SslSocketFactory.create(SslSocketFactory.java:150)
at com.google.cloud.sql.mysql.SocketFactory.connect(SocketFactory.java:47)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:300)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2251)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:140)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:148)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
... 42 more
Caused by:
java.lang.IllegalAccessError: com/google/appengine/repackaged/com/google/common/base/Platform
at com.google.appengine.repackaged.com.google.common.base.Ticker$1.read(Ticker.java:69)
at com.google.appengine.repackaged.com.google.common.base.Stopwatch.elapsedNanos(Stopwatch.java:178)
at com.google.appengine.repackaged.com.google.common.base.Stopwatch.elapsed(Stopwatch.java:191)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LoadingValueReference.elapsedNanos(LocalCache.java:3665)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.getAndRecordStats(LocalCache.java:2382)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2337)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2295)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2208)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache.get(LocalCache.java:4062)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:4066)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4995)
at com.google.appengine.repackaged.com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:5001)
at com.google.appengine.api.appidentity.AppIdentityServiceImpl.getAccessToken(AppIdentityServiceImpl.java:272)
at com.google.api.client.googleapis.extensions.appengine.auth.oauth2.AppIdentityCredential.intercept(AppIdentityCredential.java:98)
at com.google.api.client.googleapis.extensions.appengine.auth.oauth2.AppIdentityCredential$AppEngineCredentialWrapper.intercept(AppIdentityCredential.java:243)
at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:859)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:410)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:343)
at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:460)
at com.google.cloud.sql.mysql.SslSocketFactory.obtainInstanceMetadata(SslSocketFactory.java:370)
at com.google.cloud.sql.mysql.SslSocketFactory.fetchInstanceSslInfo(SslSocketFactory.java:282)
at com.google.cloud.sql.mysql.SslSocketFactory.getInstanceSslInfo(SslSocketFactory.java:262)
at com.google.cloud.sql.mysql.SslSocketFactory.createAndConfigureSocket(SslSocketFactory.java:181)
at com.google.cloud.sql.mysql.SslSocketFactory.create(SslSocketFactory.java:150)
at com.google.cloud.sql.mysql.SocketFactory.connect(SocketFactory.java:47)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:300)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2251)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:140)
at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:148)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)
at java.sql.DriverManager.getConnection(DriverManager.java:571)
at java.sql.DriverManager.getConnection(DriverManager.java:233)
at com.example.appengine.cloudsql.CloudSqlServlet.doGet(CloudSqlServlet.java:88)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:134)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:48)
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.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349)
at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116)
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:95)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:508)
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$RequestHandler.headerComplete(HttpConnection.java:923)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Powered by Jetty://
这是servlet代码
package com.example.appengine.cloudsql;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.Inet4Address;
import java.net.Inet6Address;
import java.net.InetAddress;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
// [START example]
@SuppressWarnings("serial")
public class CloudSqlServlet extends HttpServlet {
@Override
public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException,
ServletException {
String path = req.getRequestURI();
if (path.startsWith("/favicon.ico")) {
return; // ignore the request for favicon.ico
}
// store only the first two octets of a users ip address
String userIp = req.getRemoteAddr();
InetAddress address = InetAddress.getByName(userIp);
if (address instanceof Inet6Address) {
// nest indexOf calls to find the second occurrence of a character in a string
// an alternative is to use Apache Commons Lang: StringUtils.ordinalIndexOf()
userIp = userIp.substring(0, userIp.indexOf(":", userIp.indexOf(":") + 1)) + ":*:*:*:*:*:*";
} else if (address instanceof Inet4Address) {
userIp = userIp.substring(0, userIp.indexOf(".", userIp.indexOf(".") + 1)) + ".*.*";
}
GoogleCredential credential = GoogleCredential.getApplicationDefault();
final String createTableSql = "CREATE TABLE IF NOT EXISTS visits ( visit_id INT NOT NULL "
+ "AUTO_INCREMENT, user_ip VARCHAR(46) NOT NULL, timestamp DATETIME NOT NULL, "
+ "PRIMARY KEY (visit_id) )";
final String createVisitSql = "INSERT INTO visits (user_ip, timestamp) VALUES (?, ?)";
final String selectSql = "SELECT user_ip, timestamp FROM visits ORDER BY timestamp DESC "
+ "LIMIT 10";
PrintWriter out = resp.getWriter();
resp.setContentType("text/plain");
String url;
if (System
.getProperty("com.google.appengine.runtime.version").startsWith("Google App Engine/")) {
// Check the System properties to determine if we are running on appengine or not
// Google App Engine sets a few system properties that will reliably be present on a remote
// instance.
url = System.getProperty("ae-cloudsql.cloudsql-database-url");
try {
// Load the class that provides the new "jdbc:google:mysql://" prefix.
Class.forName("com.mysql.jdbc.GoogleDriver");
} catch (ClassNotFoundException e) {
throw new ServletException("Error loading Google JDBC Driver", e);
}
} else {
// Set the url with the local MySQL database connection url when running locally
url = System.getProperty("ae-cloudsql.local-database-url");
}
log("connecting to: " + url);
try (Connection conn = DriverManager.getConnection(url);
PreparedStatement statementCreateVisit = conn.prepareStatement(createVisitSql)) {
conn.createStatement().executeUpdate(createTableSql);
statementCreateVisit.setString(1, userIp);
statementCreateVisit.setTimestamp(2, new Timestamp(new Date().getTime()));
statementCreateVisit.executeUpdate();
try (ResultSet rs = conn.prepareStatement(selectSql).executeQuery()) {
out.print("Last 10 visits:\n");
while (rs.next()) {
String savedIp = rs.getString("user_ip");
String timeStamp = rs.getString("timestamp");
out.print("Time: " + timeStamp + " Addr: " + savedIp + "\n");
}
}
} catch (SQLException e) {
throw new ServletException("SQL error", e);
}
}
}
// [END example]
最佳答案
在本地开发和测试时,您有几种选择:
J7 example被配置为使用云中由 <use-google-connector-j>true</use-google-connector-j>
注入(inject)的 Google MySQL 驱动程序在 appengine-web.xml 中并将标准 MySQL 驱动程序与 Google SocketFactory 一起使用在本地运行时。
要使用您自己的本地 MySQL 实例运行,请在 WEB-INF/appengine-web.xml
中更改 ae-cloudsql.local-database-url
数据库连接字符串的属性,可能类似于:jdbc:mysql:localhost:3306/${database}?user=${user}&password=${password}&useSSL=false
(假设您更新了 pom.xml
或 mvn appengine:devserver -Duser=... -Dpassword=... -Ddatabase=... -D INSTANCE_CONNECTION_NAME=projectID:region:instance
您看到的错误是说您的连接字符串指定了一个无法识别的驱动程序。如果您确定一切正常,那么您可以尝试添加以下内容(不再需要):
try {
Class.forName("com.mysql.jdbc.Driver")
} catch (ClassNotFoundException e) {
...
}
我将运行驱动程序示例,但它应该可以工作。
关于java - 来自本地主机的谷歌云 sql 连接错误(Java eclipse),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/45238634/
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有没有在 iPad 或 iPhone 应用程序中使用 Facebook 连接。 这个想法是登录这个应用程序,然后能够看到我的哪些 facebook 用户也在使用该应用程序及其功能。 最佳答案 是的。
我在连接或打印字符串时遇到了一个奇怪的问题。我有一个 char * ,可以将其设置为字符串文字的几个值之一。 char *myStrLiteral = NULL; ... if(blah) myS
对于以下数据 - let $x := "Yahooooo !!!! Select one number - " let $y := 1 2 3 4 5 6 7 我想得到
我正在看 UDEMY for perl 的培训视频,但是视频不清晰,看起来有错误。 培训展示了如何使用以下示例连接 2 个字符串: #!usr/bin/perl print $str = "Hi";
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