如图，即使输入正确账户密码依旧错误，不知道为什么
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
public class LoginTest extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
String username = req.getParameter("username");
String password = req.getParameter("password");
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
Boolean loginFlag = false;
String realName = null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
connection = DriverManager.getConnection("jdbc:mysql://localhost" +
":3306" +
"/bjpowernode", "root", "password");
String sql = "select id,username,password,realname from t_user where username=? " +
"and password=?";
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, username);
preparedStatement.setString(2, password);
resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
loginFlag = true;
realName = resultSet.getString("realname");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException throwables) {
throwables.printStackTrace();
}
}
}
if (loginFlag) {
resp.setContentType("text/html;charset=UTF-8");
PrintWriter out = resp.getWriter();
out.print("<html>");
out.print("<head>");
out.print("<title>页面</title>");
out.print("</head>");
out.print("<body>");
out.print("welcome");
out.print(realName);
out.print("访问");
out.print("</body>");
out.print("</html>");
} else {
resp.sendRedirect(req.getContextPath() + "/LoginError");
}
}
}
错误日志没有吗？
打印一份日志看看，看看大概错在哪个流程
2021-08-01 23:02:21,157 [2615259] INFO - ij.compiler.impl.CompileDriver - COMPILATION STARTED (BUILD PROCESS)
2021-08-01 23:02:21,584 [2615686] INFO - j.compiler.server.BuildManager - BUILDER_PROCESS [stdout]: Build process started. Classpath: D:/IDEA/IntelliJ IDEA 2021.1.3/plugins/java/lib/jps-launcher.jar;D:/Java/lib/tools.jar
2021-08-01 23:02:23,859 [2617961] INFO - lij.compiler.impl.CompilerUtil - COMPILATION FINISHED (BUILD PROCESS); Errors: 0; warnings: 0 took 2708 ms: 0 min 2sec
2021-08-01 23:02:23,963 [2618065] INFO - ij.compiler.impl.CompileDriver - COMPILATION STARTED (BUILD PROCESS)
2021-08-01 23:02:23,965 [2618067] INFO - j.compiler.server.BuildManager - Using preloaded build process to compile D:/IDEA/prj-servlet-03
2021-08-01 23:02:24,127 [2618229] INFO - j.compiler.server.BuildManager - BUILDER_PROCESS [stdout]: Build process started. Classpath: D:/IDEA/IntelliJ IDEA 2021.1.3/plugins/java/lib/jps-launcher.jar;D:/Java/lib/tools.jar
2021-08-01 23:02:26,110 [2620212] INFO - lij.compiler.impl.CompilerUtil - COMPILATION FINISHED (BUILD PROCESS); Errors: 0; warnings: 0 took 2155 ms: 0 min 2sec
2021-08-01 23:02:26,394 [2620496] INFO - j.compiler.server.BuildManager - BUILDER_PROCESS [stdout]: Build process started. Classpath: D:/IDEA/IntelliJ IDEA 2021.1.3/plugins/java/lib/jps-launcher.jar;D:/Java/lib/tools.jar
2021-08-01 23:02:33,667 [2627769] INFO - tbrains.idea.tomcat.TomcatUtil - Cannot load D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
com.intellij.execution.ExecutionException: Cannot load D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
at org.jetbrains.idea.tomcat.TomcatUtil.loadXMLFile(TomcatUtil.java:209)
at org.jetbrains.idea.tomcat.TomcatUtil.findContextInContextXml(TomcatUtil.java:108)
at org.jetbrains.idea.tomcat.TomcatUtil.findContextElement(TomcatUtil.java:382)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl.addApplicationContext(TomcatAdminLocalServerImpl.java:197)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl$4.doPerform(TomcatAdminLocalServerImpl.java:128)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl$DeployStep.perform(TomcatAdminLocalServerImpl.java:283)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl.doDeploy(TomcatAdminLocalServerImpl.java:132)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$4.doPerform(JavaeeJmxAdminServerBase.java:120)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$JmxOperation.perform(JavaeeJmxAdminServerBase.java:245)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.doStartDeploy(JavaeeJmxAdminServerBase.java:135)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$2.setDeploymentStatus(JavaeeJmxAdminServerBase.java:90)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$DeploymentModelOperation.doSetDeploymentStatus(JavaeeJmxAdminServerBase.java:272)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$3.doPerform(JavaeeJmxAdminServerBase.java:100)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$JmxOperation.perform(JavaeeJmxAdminServerBase.java:245)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.doStartDeployWithUndeploy(JavaeeJmxAdminServerBase.java:107)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.startDeploy(JavaeeJmxAdminServerBase.java:74)
at org.jetbrains.idea.tomcat.admin.TomcatAdminServerBase.startDeploy(TomcatAdminServerBase.java:121)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl.startDeploy(TomcatAdminLocalServerImpl.java:102)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at com.intellij.remoteServer.agent.impl.ThreadInvocationHandler.lambda$invoke$0(ThreadInvocationHandler.java:53)
at com.intellij.remoteServer.agent.impl.ThreadInvocationHandler.lambda$invoke$1(ThreadInvocationHandler.java:97)
at com.intellij.util.concurrency.BoundedTaskExecutor.doRun(BoundedTaskExecutor.java:216)
at com.intellij.util.concurrency.BoundedTaskExecutor.access$200(BoundedTaskExecutor.java:27)
at com.intellij.util.concurrency.BoundedTaskExecutor$1.execute(BoundedTaskExecutor.java:195)
at com.intellij.util.ConcurrencyUtil.runUnderThreadName(ConcurrencyUtil.java:213)
at com.intellij.util.concurrency.BoundedTaskExecutor$1.run(BoundedTaskExecutor.java:184)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:668)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:665)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1.run(Executors.java:665)
at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.io.FileNotFoundException: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
at java.base/java.io.FileInputStream.open0(Native Method)
at java.base/java.io.FileInputStream.open(FileInputStream.java:219)
at java.base/java.io.FileInputStream.(FileInputStream.java:157)
at org.jetbrains.idea.tomcat.TomcatUtil.loadXMLFile(TomcatUtil.java:204)
... 35 more
2021-08-01 23:02:33,672 [2627774] INFO - tbrains.idea.tomcat.TomcatUtil - Cannot load D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
com.intellij.execution.ExecutionException: Cannot load D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
at org.jetbrains.idea.tomcat.TomcatUtil.loadXMLFile(TomcatUtil.java:209)
at org.jetbrains.idea.tomcat.TomcatUtil.findContextInContextXml(TomcatUtil.java:108)
at org.jetbrains.idea.tomcat.TomcatUtil.findContextElement(TomcatUtil.java:382)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl$4.doPerform(TomcatAdminLocalServerImpl.java:129)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl$DeployStep.perform(TomcatAdminLocalServerImpl.java:283)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl.doDeploy(TomcatAdminLocalServerImpl.java:132)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$4.doPerform(JavaeeJmxAdminServerBase.java:120)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$JmxOperation.perform(JavaeeJmxAdminServerBase.java:245)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.doStartDeploy(JavaeeJmxAdminServerBase.java:135)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$2.setDeploymentStatus(JavaeeJmxAdminServerBase.java:90)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$DeploymentModelOperation.doSetDeploymentStatus(JavaeeJmxAdminServerBase.java:272)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$3.doPerform(JavaeeJmxAdminServerBase.java:100)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase$JmxOperation.perform(JavaeeJmxAdminServerBase.java:245)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.doStartDeployWithUndeploy(JavaeeJmxAdminServerBase.java:107)
at com.intellij.javaee.oss.admin.jmx.JavaeeJmxAdminServerBase.startDeploy(JavaeeJmxAdminServerBase.java:74)
at org.jetbrains.idea.tomcat.admin.TomcatAdminServerBase.startDeploy(TomcatAdminServerBase.java:121)
at org.jetbrains.idea.tomcat.admin.TomcatAdminLocalServerImpl.startDeploy(TomcatAdminLocalServerImpl.java:102)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at com.intellij.remoteServer.agent.impl.ThreadInvocationHandler.lambda$invoke$0(ThreadInvocationHandler.java:53)
at com.intellij.remoteServer.agent.impl.ThreadInvocationHandler.lambda$invoke$1(ThreadInvocationHandler.java:97)
at com.intellij.util.concurrency.BoundedTaskExecutor.doRun(BoundedTaskExecutor.java:216)
at com.intellij.util.concurrency.BoundedTaskExecutor.access$200(BoundedTaskExecutor.java:27)
at com.intellij.util.concurrency.BoundedTaskExecutor$1.execute(BoundedTaskExecutor.java:195)
at com.intellij.util.ConcurrencyUtil.runUnderThreadName(ConcurrencyUtil.java:213)
at com.intellij.util.concurrency.BoundedTaskExecutor$1.run(BoundedTaskExecutor.java:184)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:668)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1$1.run(Executors.java:665)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.util.concurrent.Executors$PrivilegedThreadFactory$1.run(Executors.java:665)
at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.io.FileNotFoundException: D:\IDEA\prj-servlet-03\out\artifacts\prj_servlet_03_war_exploded\META-INF\context.xml (系统找不到指定的路径。)
at java.base/java.io.FileInputStream.open0(Native Method)
at java.base/java.io.FileInputStream.open(FileInputStream.java:219)
at java.base/java.io.FileInputStream.(FileInputStream.java:157)
at org.jetbrains.idea.tomcat.TomcatUtil.loadXMLFile(TomcatUtil.java:204)
... 34 more
2021-08-01 23:02:44,176 [2638278] INFO - j.ide.actions.RevealFileAction - Exit code 1
到if判断那一步正常来说应该会将loginFlag值重新赋为true，但是没有，我就很不明白。。
先提前感谢大佬们~
首先，你这报错日志是找不到文件啊大哥，这种报错你项目能正常启动？建议你确定项目是否正常启动，打个断点看看sql语句以及参数是否正常(把sql复制到你的sql图形化管理工具上执行一次)，代码不会按你想的走，只会按你写的走。