Java FAQ
javac 乱码
强制使用 UTF-8
javac -J-Dfile.encoding=UTF-8
环境变量
- JAVA_TOOL_OPTIONS
- java, javac, jar 会用
- 例如
-agentlib:hprof
- JVMTI 定义
_JAVA_OPTIONS
- 类似 JAVA_TOOL_OPTIONS,但优先级更高
- 针对 Hotspot
- JAVA_OPTS
- 由其他工具使用
- java 不用
- JDK_JAVA_OPTIONS
- jdk9+
- 类似 JAVA_TOOL_OPTIONS,但只有 java 会用
- java
- JAVA_HOME
Property
file.encoding=UTF-8
user.language=en
user.country=US
user.variant=
java.io.tmpdir=
javax.net.ssl.keyStore=
javax.net.ssl.keyStorePassword=
javax.net.ssl.keyStoreType=
javax.net.ssl.trustStore=
javax.net.ssl.trustStorePassword=
javax.net.ssl.trustStoreType=
com.sun.management.jmxremote=
选择 JUL 类逻辑
Why is generic of a return type erased when there is an unchecked conversion of a method parameter in Java 8?
Collection http://fastutil.di.unimi.it/ http://pcollections.org/ https://github.com/hrldcpr/pcollections
https://mvnrepository.com/artifact/org.eclipse.collections/eclipse-collections https://github.com/eclipse/eclipse-collections
https://mvnrepository.com/open-source/collections
<dependency>
<groupId>com.carrotsearch</groupId>
<artifactId>hppc</artifactId>
<version>0.8.1</version>
</dependency>
https://github.com/carrotsearch/hppc
Proxy performance
https://stackoverflow.com/q/1856242/1870054
deploy
-Dspring.profiles.active=development
SPRING_PROFILES_ACTIVE