What's the difference between 「adb logcat」in terminal and executing「Runtime.getRuntime.exec(“logcat”)」in apps?

Question

One way is to show logs in Windows cmd, and another is to print in the app. What's the differences(or range？) of logs i get because they are all logs from the system. And I also noticed that the logs in cmd here have four different types like "beginning of main""beginning of kernel""beginning of system" which I don't get in the second way. What are they？

Answer 1

Generally, they are both the same.
But actually, you could input adb logcat "*:E" into your console to filter ERROR (the prefix as 'E/') level logs.
Plus, 'V' for VERBOSE, 'D' for DEBUG, 'I' for INFO, 'W' for WARN, 'A' for ASSERT.