Java NoClassDefFoundError，但存在类

我的Jar文件

  cassandra-driver-core-2.1.0.jar

com/datastax/driver/core/Cluster的myjavap命令

它表明

 public class com.datastax.driver.core.Cluster implements java.io.Closeable {
 final com.datastax.driver.core.Cluster$Manager manager;
 protected com.datastax.driver.core.Cluster(java.lang.String, java.util.List<java.net.InetSocketAddress>, com.datastax.driver.core.Configuration);
 protected com.datastax.driver.core.Cluster(com.datastax.driver.core.Cluster$Initializer);
 public com.datastax.driver.core.Cluster init();
 public static com.datastax.driver.core.Cluster buildFrom(com.datastax.driver.core.Cluster$Initializer);
 public static com.datastax.driver.core.Cluster$Builder builder();
 ...............

我的编译命令是

   javac -classpath cassandra-driver-core-2.1.0.jar SimpleClient.java

我的运行命令

   tried1:   java  -classpath cassandra-driver-core-2.1.0.jar SimpleClient

说

但是课堂上有

  Tried2:  java  -classpath SimpleClient

上面说

  Obj Created
  I am in
  Exception in thread "main" java.lang.NoClassDefFoundError: com/datastax/driver/core/Cluster
    at SimpleClient.connect(SimpleClient.java:12)
    at SimpleClient.main(SimpleClient.java:29)
   Caused by: java.lang.ClassNotFoundException: com.datastax.driver.core.Cluster

请告诉我解决方案。

您必须使用

java  -classpath ./;cassandra-driver-core-2.1.0.jar SimpleClient

在windows计算机上

或

在linux机器上

这将把实际目录添加到类路径中

  Tried2:  java  -classpath SimpleClient

  Obj Created
  I am in
  Exception in thread "main" java.lang.NoClassDefFoundError: com/datastax/driver/core/Cluster
    at SimpleClient.connect(SimpleClient.java:12)
    at SimpleClient.main(SimpleClient.java:29)
   Caused by: java.lang.ClassNotFoundException: com.datastax.driver.core.Cluster

java  -classpath ./;cassandra-driver-core-2.1.0.jar SimpleClient

java  -classpath ./:cassandra-driver-core-2.1.0.jar SimpleClient