RocketMQ使用命令查看主题列表报错：SubCommandException: TopicListSubCommand command failed

org.apache.rocketmq.tools.command.SubCommandException: TopicListSubCommand command failed
	at org.apache.rocketmq.tools.command.topic.TopicListSubCommand.execute(TopicListSubCommand.java:113)
	at org.apache.rocketmq.tools.command.MQAdminStartup.main0(MQAdminStartup.java:140)
	at org.apache.rocketmq.tools.command.MQAdminStartup.main(MQAdminStartup.java:91)
Caused by: org.apache.rocketmq.acl.common.AclException: [10015:signature-failed] unable to calculate a request signature. error=[10015:signature-failed] unable to calculate a request signature. error=Algorithm HmacSHA1 not available
	at org.apache.rocketmq.acl.common.AclSigner.signAndbase64Encode(AclSigner.java:84)
	at org.apache.rocketmq.acl.common.AclSigner.calSignature(AclSigner.java:73)
	at org.apache.rocketmq.acl.common.AclSigner.calSignature(AclSigner.java:68)
	at org.apache.rocketmq.acl.common.AclUtils.calSignature(AclUtils.java:69)
	at org.apache.rocketmq.acl.common.AclClientRPCHook.doBeforeRequest(AclClientRPCHook.java:44)
	at org.apache.rocketmq.remoting.netty.NettyRemotingAbstract.doBeforeRpcHooks(NettyRemotingAbstract.java:172)
	at org.apache.rocketmq.remoting.netty.NettyRemotingClient.invokeSync(NettyRemotingClient.java:372)
	at org.apache.rocketmq.client.impl.MQClientAPIImpl.getTopicListFromNameServer(MQClientAPIImpl.java:1392)
	at org.apache.rocketmq.tools.admin.DefaultMQAdminExtImpl.fetchAllTopicList(DefaultMQAdminExtImpl.java:253)
	at org.apache.rocketmq.tools.admin.DefaultMQAdminExt.fetchAllTopicList(DefaultMQAdminExt.java:218)
	at org.apache.rocketmq.tools.command.topic.TopicListSubCommand.execute(TopicListSubCommand.java:107)
	... 2 more
Caused by: org.apache.rocketmq.acl.common.AclException: [10015:signature-failed] unable to calculate a request signature. error=Algorithm HmacSHA1 not available
	at org.apache.rocketmq.acl.common.AclSigner.sign(AclSigner.java:63)
	at org.apache.rocketmq.acl.common.AclSigner.signAndbase64Encode(AclSigner.java:79)
	... 12 more
Caused by: java.security.NoSuchAlgorithmException: Algorithm HmacSHA1 not available
	at javax.crypto.Mac.getInstance(Mac.java:181)
	at org.apache.rocketmq.acl.common.AclSigner.sign(AclSigner.java:57)
	... 13 more

1.进入rocketmq的bin目录下：/software/rocketmq/rocketmq-all-4.8.0-bin-release，
/software/rocketmq/rocketmq-all-4.8.0-bin-release是我自己的安装路径。
2.用vim tools.sh打开tools.sh.在JAVA_OPT配置中，在-Djava.ext.dirs一行最后面添加ext的路径，我的ext路径如下：

修改前：

JAVA_OPT="${JAVA_OPT} -server -Xms1g -Xmx1g -Xmn256m -XX:metaspaceSize=128m -XX:MaxmetaspaceSize=128m"
JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${base_DIR}/lib:${JAVA_HOME}/jre/lib/ext:${JAVA_HOME}/lib/ext"
JAVA_OPT="${JAVA_OPT} -cp ${CLASSPATH}"

修改后：

JAVA_OPT="${JAVA_OPT} -server -Xms1g -Xmx1g -Xmn256m -XX:metaspaceSize=128m -XX:MaxmetaspaceSize=128m"
JAVA_OPT="${JAVA_OPT} -Djava.ext.dirs=${base_DIR}/lib:${JAVA_HOME}/jre/lib/ext:${JAVA_HOME}/lib/ext:/usr/java/jdk1.8.0_121/jre/lib/ext"
JAVA_OPT="${JAVA_OPT} -cp ${CLASSPATH}"

看RocketMQbin目录下的tools.sh文件，其中有那么一句话：

所以我们可以通过修改/etc/profile文件，在其中添加JAVA_HOME变量，值为java的安装目录；并且export导出JAVA_HOME变量，使得其他Linux进程可以获取到JAVA_HOME变量

再次执行命令：

sh ./bin/mqadmin topicList

很尴尬，又出异常了；我们看看异常信息，感觉是因为我没指定NameServer地址的原因。
我们指定nameServer地址再试试：

sh ./mqadmin topicList -n 127.0.0.1:9876

成功获取到Topic的列表。