我正尝试在Windows机器上安装Cassandra，使用Java 1. 8。我收到的错误消息如下：
ERROR [main] 2023-01-27 09:45:26,820 FileUtils.java:80 - Cannot initialize un-mmaper. (Are you using a non-Oracle JVM?) Compacted data files will not be removed promptly. Consider using an Oracle JVM or using standard disk access mode
java.lang.IllegalAccessError: class org.apache.cassandra.io.util.FileUtils (in unnamed module @0x6aa8e115) cannot access class sun.nio.ch.DirectBuffer (in module java.base) because module java.base does not export sun.nio.ch to unnamed module @0x6aa8e115
at org.apache.cassandra.io.util.FileUtils.<clinit>(FileUtils.java:75)
at org.apache.cassandra.config.DatabaseDescriptor.guessFileStore(DatabaseDescriptor.java:1093)
at org.apache.cassandra.config.DatabaseDescriptor.applySimpleConfig(DatabaseDescriptor.java:493)
at org.apache.cassandra.config.DatabaseDescriptor.applyAll(DatabaseDescriptor.java:324)
at org.apache.cassandra.config.DatabaseDescriptor.daemonInitialization(DatabaseDescriptor.java:153)
at org.apache.cassandra.config.DatabaseDescriptor.daemonInitialization(DatabaseDescriptor.java:137)
at org.apache.cassandra.service.CassandraDaemon.applyConfig(CassandraDaemon.java:680)
at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:622)
at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:786)
INFO [main] 2023-01-27 09:45:26,944 RateBasedBackPressure.java:123 - Initialized back-pressure with high ratio: 0.9, factor: 5, flow: FAST, window size: 2000.
INFO [main] 2023-01-27 09:45:26,945 DatabaseDescriptor.java:781 - Back-pressure is disabled with strategy org.apache.cassandra.net.RateBasedBackPressure{high_ratio=0.9, factor=5, flow=FAST}.
Exception (java.lang.IllegalAccessError) encountered during startup: superclass access check failed: class org.apache.cassandra.utils.JMXServerUtils$JmxRegistry (in unnamed module @0x6aa8e115) cannot access class sun.rmi.registry.RegistryImpl (in module java.rmi) because module java.rmi does not export sun.rmi.registry to unnamed module @0x6aa8e115
java.lang.IllegalAccessError: superclass access check failed: class org.apache.cassandra.utils.JMXServerUtils$JmxRegistry (in unnamed module @0x6aa8e115) cannot access class sun.rmi.registry.RegistryImpl (in module java.rmi) because module java.rmi does not export sun.rmi.registry to unnamed module @0x6aa8e115
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1013)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:862)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:760)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:681)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:639)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at org.apache.cassandra.utils.JMXServerUtils.createJMXServer(JMXServerUtils.java:80)
at org.apache.cassandra.service.CassandraDaemon.maybeInitJmx(CassandraDaemon.java:159)
at org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:204)
at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:633)
at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:786)
ERROR [main] 2023-01-27 09:45:27,067 CassandraDaemon.java:803 - Exception encountered during startup
java.lang.IllegalAccessError: superclass access check failed: class org.apache.cassandra.utils.JMXServerUtils$JmxRegistry (in unnamed module @0x6aa8e115) cannot access class sun.rmi.registry.RegistryImpl (in module java.rmi) because module java.rmi does not export sun.rmi.registry to unnamed module @0x6aa8e115
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1013)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:862)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:760)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:681)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:639)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at org.apache.cassandra.utils.JMXServerUtils.createJMXServer(JMXServerUtils.java:80)
at org.apache.cassandra.service.CassandraDaemon.maybeInitJmx(CassandraDaemon.java:159)
at org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:204)
at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:633)
at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:786)之后它与消息一起存在：主要完成。
有人能帮我吗？
1条答案
按热度按时间qhhrdooz1#
兼容性
多条
IllegalAccessError消息向我表明，您正在运行一个不受支持的Java版本，该版本与Cassandra不兼容。您说您正在运行Java 8，但有可能您的计算机上安装了较新的版本，并且
JAVA_HOME指向较新的版本。Java支持
Cassandra 3.0/3.11及更早版本仅支持Java 8。Cassandra 4.0增加了对Java 11 LTS（CASSANDRA-9608）的支持，因此C* 4.x可以与Java 8或Java 11一起使用。
如果你安装了一个受支持的Java版本，我发现一些Java风格似乎与Cassandra不兼容。我的建议是安装一个TCK认证的Java风格，如Oracle JVM或OpenJDK。
Windows支持
值得一提的是，Cassandra使用的Java文件I/O库在Windows上一直存在问题，特别是在NTFS上。它一直是用户问题的来源，我们认为继续支持它对项目不利（参见discussion in this thread）。
我们最终在Cassandra 4.0中完全放弃了Windows支持（CASSANDRA-16171）。
备选方案
建议Windows用户使用的解决方法包括：
另外，如果你只是想学习如何在Cassandra上构建应用程序，Astra DB有一个免费的层，你可以在那里启动一个集群，只需点击5次，不需要信用卡。