Hello Team,

I faced a performance issue that the prompt was not shown for a long time when I ran SQLLine in eclipse-temurin:8-jdk-noble container.

It seems that the root cause of this issue exists on the JLine side. So, I want to update the version of JLine that SQLLine uses.

I will submit a new PR. However, I'm not familiar with the rules of this repository. So, could you please correct me if I wrong something?

The issue details are the following:

Overview

When I run SQLLine in the eclipse-temurin:8-jdk-noble container, the prompt does not appear for a long time.

# java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar

(The prompt "sqlline>" does not appear for a long time...)

How to reproduce the issue

1. Start eclipse-temurin:8-jdk-noble container.

   docker run -d --name sqlline-test --entrypoint sleep eclipse-temurin:8-jdk-noble inf

2. Run bash in the container.

   docker exec -it sqlline-test bash

3. Install the git command.

   apt update && apt install -y git

4. Build SQLLine based on the current main branch.

   git clone https://github.com/julianhyde/sqlline.git
   cd sqlline
   LS_COLORS="" ./mvnw package

5. Run SQLLine in the container.

   java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar

   The prompt does not appear for a long time...

Issue details

I checked what is happening in the internal of SQLLine by using the jdb command when the issue occurs. As a result, it seems that java.util.regex.Pattern runs many times and it takes a long time.

• Stack of SQLLine when the issue occurs.

  main[1] where
    [1] java.util.regex.Pattern$Curly.match (Pattern.java:4,241)
    [2] java.util.regex.Pattern$Branch.match (Pattern.java:4,618)
    [3] java.util.regex.Pattern$GroupHead.match (Pattern.java:4,672)
    [4] java.util.regex.Pattern$BmpCharProperty.match (Pattern.java:3,812)
    [5] java.util.regex.Pattern$GroupHead.match (Pattern.java:4,672)
  
    (omit)
  
    [2,995] java.util.regex.Pattern$Curly.match0 (Pattern.java:4,261)
    [2,996] java.util.regex.Pattern$Curly.match (Pattern.java:4,248)
    [2,997] java.util.regex.Pattern$Branch.match (Pattern.java:4,618)
    [2,998] java.util.regex.Pattern$GroupHead.match (Pattern.java:4,672)
    [2,999] java.util.regex.Matcher.match (Matcher.java:1,270)
    [3,000] java.util.regex.Matcher.matches (Matcher.java:604)
    [3,001] java.util.regex.Pattern.matches (Pattern.java:1,135)
    [3,002] java.lang.String.matches (String.java:2,121)
    [3,003] org.jline.builtins.Styles.consoleOption (Styles.java:74)
    [3,004] org.jline.builtins.Styles.style (Styles.java:51)
    [3,005] org.jline.builtins.Styles.lsStyle (Styles.java:35)
    [3,006] org.jline.builtins.Completers$FileNameCompleter.<clinit> (Completers.java:333)
    [3,007] sqlline.Application.getCommandHandlers (Application.java:254)
    [3,008] sqlline.SqlLine$Config.<init> (SqlLine.java:2,044)
    [3,009] sqlline.SqlLine.setAppConfig (SqlLine.java:1,973)
    [3,010] sqlline.SqlLine.<init> (SqlLine.java:231)
    [3,011] sqlline.SqlLine.start (SqlLine.java:268)
    [3,012] sqlline.SqlLine.main (SqlLine.java:208)

And, the java.util.regex.Pattern is called by JLine. So, I investigated this issue on the JLine side. As a result, I found the following PR. This issue has already been reported and fixed on the JLine side.

• Optimize Styles.isStylePattern() to avoid StackOverflowError jline/jline3#817

Also, the above fix is released in JLine 3.23.0. However, the latest SQLLine (1.2.0 and 1.13.0-SNAPSHOT) uses JLine 3.21.0. So, I think we can fix this issue by using the latest JLine in SQLLine.

Temporary workaround

According to the PR of JLine, the issue occurs when JLine runs java.lang.String.matches against the value of LS_COLORS.

So, I tried to set an empty string to LS_COLORS as follows:

LS_COLORS="" java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar

As a result, I was able to see the prompt soon as follows:

LS_COLORS="" java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar
sqlline version 1.13.0-SNAPSHOT
sqlline>

I think we can use this way as a temporary workaround.

My proposal

I updated the version of JLine to apply the fix of JLine as follows:

• Update the version of JLine.

  diff --git a/pom.xml b/pom.xml
  index 3f09322..740fe66 100644
  --- a/pom.xml
  +++ b/pom.xml
  @@ -31,7 +31,7 @@
       <h2.version>2.1.210</h2.version>
       <hamcrest.version>2.2</hamcrest.version>
       <hsqldb.version>2.5.0</hsqldb.version>
  -    <jline.version>3.21.0</jline.version>
  +    <jline.version>3.26.3</jline.version>
       <jmockit.version>1.49</jmockit.version>
       <junit.version>5.8.1</junit.version>
       <maven-assembly-plugin.version>3.3.0</maven-assembly-plugin.version>

• Run SQLLine with JLine 3.26.3.

  root@87bebc5e1fbe:/sqlline# java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar
  Nov 16, 2024 6:55:03 AM org.jline.utils.Log logr
  WARNING: The terminal provider jansi has been deprecated, check your configuration. This warning can be disabled by setting the system property org.jline.terminal.disableDeprecatedProviderWarning to true.
  sqlline version 1.13.0-SNAPSHOT
  sqlline>

As shown above, I was able to run the SQLLine, and the prompt appeared soon. However, there was a WARNING message. It seems that the JANSI is now deprecated on the JLine side. So, according to the document of JLine, I added JNI as follows:

• Update the version of JLine and add JNI in addition to JANSI.

  diff --git a/pom.xml b/pom.xml
  index 3f09322..f78bbf1 100644
  --- a/pom.xml
  +++ b/pom.xml
  @@ -31,7 +31,7 @@
       <h2.version>2.1.210</h2.version>
       <hamcrest.version>2.2</hamcrest.version>
       <hsqldb.version>2.5.0</hsqldb.version>
  -    <jline.version>3.21.0</jline.version>
  +    <jline.version>3.26.3</jline.version>
       <jmockit.version>1.49</jmockit.version>
       <junit.version>5.8.1</junit.version>
       <maven-assembly-plugin.version>3.3.0</maven-assembly-plugin.version>
  @@ -357,6 +357,11 @@
         <artifactId>jline-terminal-jansi</artifactId>
         <version>${jline.version}</version>
       </dependency>
  +    <dependency>
  +      <groupId>org.jline</groupId>
  +      <artifactId>jline-terminal-jni</artifactId>
  +      <version>${jline.version}</version>
  +    </dependency>
       <dependency>
         <groupId>org.jline</groupId>
         <artifactId>jline-terminal-jna</artifactId>

• Run SQLLine with JLine 3.26.3 and JNI.

  root@87bebc5e1fbe:/sqlline# java -jar ./target/sqlline-1.13.0-SNAPSHOT-jar-with-dependencies.jar
  sqlline version 1.13.0-SNAPSHOT
  sqlline>

As a result, the WARNING message is not shown. So, I think it would be better to update the version of JLine to resolve the issue and add JNI to avoid the WARNING message.

That's all.
Regards,