How can we customize how JShell is launched in Java 9?

JShell is an interactive REPL tool for executing and evaluating simple Java programs, such as variable declarations, statements , expressions, etc. p>

When the JShell tool starts, the code is preloaded by default. To display this code we simply start the command "/list -start". You can ask JShell to automatically load them on startup using the following command: "/set start [-retain] [Type]". The first option "-retain" tells JShell to record the [Type] required to start the next JShell session. If we don't specify, the default start can be started when opening a new session

  <strong>/set start [-retain] -File
  /set start [-retain] -Default
  /set start [-retain] -none</strong>

• /set start [-retain] File: This command tells JShell that the file must be loaded on startup The content (the file contains the following code) creates variables, methods, classes , etc.).
• /set start [-retain] -none: This command tells JShell not to load any code/commands on startup.
• /set start [-retain] -Default: This command resets the startup of JShell to its default value.

In the following code snippet, we can use the "/set start [-retain] -File" command,

<strong>jshell> /list -start

  s1 : import java.io.*;
  s2 : import java.math.*;
  s3 : import java.net.*;
  s4 : import java.nio.file.*;
  s5 : import java.util.*;
  s6 : import java.util.concurrent.*;
  s7 : import java.util.function.*;
  s8 : import java.util.prefs.*;
  s9 : import java.util.regex.*;
  s10 : import java.util.stream.*;

jshell> /set start -retain save.jsh

jshell> /exit
|   Goodbye

C:\Users\User>jshell
|   Welcome to JShell -- Version 9.0.4
|   For an introduction type: /help intro

jshell> /list -start

  s1 : int x = 20;
  s2 : double y = 30;
  s3 : public int sum(int a, int b) {
          return a + b;
       }
  s4 : String str = "TutorialsPoint";</strong>

In the following code snippet, we can use the "/set start [-retain] -none" command.

<strong>jshell> /set start -retain -none

jshell> /exit
|   Goodbye

C:\Users\User>jshell
|   Welcome to JShell -- Version 9.0.4
|   For an introduction type: /help intro

jshell> /list -start</strong>

In the following code snippet, we can use the "/set start [-retain] -Default" command.

<strong>jshell> /set start -retain -default

jshell> /exit
|   Goodbye

C:\Users\User>jshell
|   Welcome to JShell -- Version 9.0.4
|   For an introduction type: /help intro

jshell> /list -start

  s1 : import java.io.*;
  s2 : import java.math.*;
  s3 : import java.net.*;
  s4 : import java.nio.file.*;
  s5 : import java.util.*;
  s6 : import java.util.concurrent.*;
  s7 : import java.util.function.*;
  s8 : import java.util.prefs.*;
  s9 : import java.util.regex.*;
  s10 : import java.util.stream.*;</strong>

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