使用jmeter测试java协议脚本时要注意以下几点:
1. jar包的方式路径一定是这样，否则可能会出现诡异问题:
apache-jmeter
-- lib —— 脚本依赖的包放在这里
-- ext —— 自己开发脚本（jar文件）放在这里
2. jmeter/lib目录下本身有很多jar包，所以拷贝脚本依赖的jar时一定要小心，千万别和这些jmeter自带的重复，否则也会死的很难看！
附上官方白皮书：
JMeter automatically finds classes from jars in the following directories:
JMETER_HOME/lib - used for utility jars
JMETER_HOME/lib/ext - used for JMeter components and plugins
If you have developed new JMeter components, then you should jar them and copy the jar into JMeter's lib/ext directory. JMeter will automatically find JMeter components in any jars found here. Do not use lib/ext for utility jars or dependency jars used by the plugins; it is only intended for JMeter components and plugins.
If you don't want to put JMeter plugin jars in the lib/ext directory, then define the property search_paths in jmeter.properties.
Utility and dependency jars (libraries etc) can be placed in the lib directory.
If you don't want to put such jars in the lib directory, then define the property user.classpath or plugin_dependency_paths in jmeter.properties. See below for an explanation of the differences.
Other jars (such as JDBC, JMS implementations and any other support libaries needed by the JMeter code) should be placed in the lib directory - not the lib/extdirectory, or added to user.classpath .
Note: JMeter will only find .jar files, not .zip.
You can also install utility Jar files in $JAVA_HOME/jre/lib/ext, or you can set the property user.classpath in jmeter.properties
Note that setting the CLASSPATH environment variable will have no effect. This is because JMeter is started with "java -jar", and the java command silently ignores the CLASSPATH variable, and the -classpath/-cp options when -jar is used. [This occurs with all Java programs, not just JMeter.]