解决方法：

/usr/libexec/java_home -V

Matching Java Virtual Machines (2):

    1.8.144.01 (x86_64) "Oracle Corporation" - "Java" /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home

    1.8.0_144 (x86_64) "Oracle Corporation" - "Java SE 8"  /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home

/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home

vim /Applications/mat.app/Contents/Eclipse/MemoryAnalyzer.ini ，新增 vm 配置

-vm

/Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home/bin/java

重启 MAT，搞定。