arthas/tutorials/katacoda/arthas-advanced-en/options.md

There are some switches in Arthas that can be viewed with the options{{execute T2}} command.

View the value of a single option, such as

options unsafe{{execute T2}}

Allow to enhance the classes of JDK

By default, unsafe is false, ie commands such as watch/trace do not enhance the JVM class, which is the class starting with java.*.

To enhance the classes in the JVM, execute options unsafe true{{execute T2}} to set unsafe to true.

Print objects in JSON format

When json-format is false, the output is:

$ ognl '#value1=@System@getProperty("java.home"), #value2=@System@getProperty("java.runtime.name"), {#value1, #value2}'
@ArrayList[
    @String[/usr/lib/jvm/java-8-oracle/jre],
    @String[Java(TM) SE Runtime Environment],
]

options json-format true{{execute T2}}

When json-format is true, the output is:

$ ognl '#value1=@System@getProperty("java.home"), #value2=@System@getProperty("java.runtime.name"), {#v["/usr/lib/jvm/java-8-oracle/jre","Java(TM) SE Runtime Environment"]