嵌入式tomcat的使用

• • 引入pom依赖
  • 创建tomcat启动类
  • 常见问题

		8.5.72
		
		
            org.apache.tomcat.embed
            tomcat-embed-core
            ${tomcat.version}
        
        
            org.apache.tomcat.embed
            tomcat-embed-el
            ${tomcat.version}
        
        
            org.apache.tomcat.embed
            tomcat-embed-jasper
            ${tomcat.version}
        

import org.apache.catalina.startup.Tomcat;

import java.io.File;

public class ApplicationStart {

    private static void startSimpleTomcat() throws Exception {
        Tomcat tomcat = new Tomcat();
        tomcat.setPort(8090);
        String contextPath = "/myTest";
        String docbase = new File("").getAbsolutePath() + "/src/main/webapp";
        tomcat.addWebapp(contextPath, docbase);
        tomcat.start();
        tomcat.getServer().await();
    }

    public static void main(String[] args) throws Exception {
        ApplicationStart.startSimpleTomcat();
    }
}

1. 版本不兼容
   假如你使用了低版本的tomcat，可能会报各种jar包解析不了，比如json包

Unable to process Jar entry [module-info.class] from Jar [file:/D:/MavenRepository/com/fasterxml/jackson/datatype/jackson-datatype-jdk8/2.10.1/jackson-datatype-jdk8-2.10.1.jar] for annotations
org.apache.tomcat.util.bcel.classfile.ClassFormatException: Invalid byte tag in constant pool: 19
解决方法：
使用8.5.72版本，亲测有效
2. 跟spring-boot-starter-web内嵌的tomcat冲突

Caused by: java.lang.NoClassDefFoundError: javax/servlet/GenericFilter
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)

解决方法：
排除掉spring-boot-starter-tomcat

		
            org.springframework.boot
            spring-boot-starter-web
            
                
                    org.springframework.boot
                    spring-boot-starter-tomcat
                
            
            2.2.2.RELEASE