Java Project

Java projects are used to deploy Spring Boot, Tomcat, and other Java applications.

Prerequisites

1. Install Java runtime environment: Applications > Runtime Environment > Java (Amazon Corretto, a production-ready OpenJDK distribution)
2. Packaged JAR file or WAR file

Deploy Spring Boot Application

Package Project

# Maven
mvn clean package -DskipTests

# Gradle
./gradlew build -x test

Upload and Deploy

1. Upload the JAR file to the server (e.g., /opt/ace/projects/myapp/app.jar)
2. Go to the Project page, open the Java tab, and click Create Project
3. Fill in the configuration:
   • Project Name: myapp (used as the service identifier)
   • Project Directory: leave empty to default to /opt/ace/projects/<project name>, or pick a directory
   • Java Version: select an installed JDK version (the start command is generated using java<version>, e.g. java21)
   • Framework: choose a preset (Spring Boot (JAR), Spring Boot (WAR), Quarkus, Micronaut, Vert.x, Dropwizard) to auto-fill the start command, or keep Custom to enter it manually
   • Run User: defaults to www (you may also choose root/nobody or enter a custom user)
   • Start Command: auto-filled from the options above, editable (e.g., java21 -jar app.jar)
4. Enable Reverse Proxy and fill in the Domain and Project Port to automatically create a reverse proxy website for external access

Framework Presets

Selecting a Framework auto-fills the Start Command by combining java<version> with the preset's arguments. Choosing Custom leaves the command empty so you can write it yourself. The following presets are available:

Framework	Generated Command (with java21)
Custom	(empty, enter manually)
Spring Boot (JAR)	java21 -jar app.jar
Spring Boot (WAR)	java21 -jar app.war
Quarkus	java21 -jar quarkus-run.jar
Micronaut	java21 -jar app.jar
Vert.x	java21 -jar app.jar
Dropwizard	java21 server config.yml

The generated command is only a starting point. Rename the artifact to match your build output (e.g. myapp-1.0.0.jar) and append any JVM parameters or application arguments before saving.

Start Command Examples

# Basic startup
java21 -jar app.jar

# Specify configuration file
java21 -jar app.jar --spring.profiles.active=prod

# Set JVM parameters
java21 -Xms512m -Xmx1024m -jar app.jar

# Specify port
java21 -jar app.jar --server.port=8080

JVM Parameter Recommendations

# Recommended production environment configuration
java21 \
  -Xms512m \
  -Xmx1024m \
  -XX:+UseG1GC \
  -XX:MaxGCPauseMillis=200 \
  -jar app.jar

Common parameter descriptions:

Parameter	Description
-Xms	Initial heap memory size
-Xmx	Maximum heap memory size
-XX:+UseG1GC	Use G1 garbage collector
-XX:MaxGCPauseMillis	Maximum GC pause time

Multiple JDK Versions

AcePanel supports installing multiple JDK versions side by side, with binaries under /opt/ace/server/java/{version}/bin/. Each installed version exposes a java{version} command (e.g. java21) so you can pin a project to a specific JDK.

On a Java runtime environment's management page, click Set as CLI Default Version to symlink that version's java, javac, jar, and jshell binaries into /usr/local/bin, making them the default unversioned commands.

Manage Project

After creation, each project appears as a row on the Project page (filter by the Java tab) showing its name, type, run status (Running / Stopped / Failed), autostart state, and directory. The following actions are available per row:

• Start / Stop: start or stop the service immediately
• Restart: restart a running service (shown only when running)
• Reload: reload a running service without a full restart (shown only when running)
• Logs: open a real-time log viewer for the service
• Autostart: toggle whether the service starts automatically on boot
• Edit: open the project editor (see below)
• Delete: remove the project and its systemd unit; this requires a 5-second confirmation

You can also select multiple projects and use the top Delete button for bulk deletion (also guarded by a 5-second confirmation).

Edit Project

The Edit dialog organizes the systemd unit settings into tabs:

• Basic Settings: project name, description, project directory, working directory, and run user
• Runtime Settings: start command, pre-start / post-start / stop / reload commands, restart strategy, restart interval, max restarts, start/stop timeouts, standard output / standard error targets (journal, syslog, kmsg, null, or a file), and environment variables
• Dependencies: systemd ordering and dependency directives (Requires, Wants, After, Before), e.g. mysqld.service, redis.service
• Resource Limits: memory limit (MB, 0 for unlimited) and CPU quota (e.g. 50%, 200%)
• Security Settings: NoNewPrivileges, ProtectHome, ProtectSystem, /tmp protection, and read-write / read-only path lists

Saving regenerates the underlying systemd unit at /etc/systemd/system/<project name>.service and reloads it.

Process Management

AcePanel uses systemd to manage Java processes, automatically handling:

• Automatic restart on process crash (per the configured restart strategy)
• Automatic startup on boot (when autostart is enabled)
• Log recording

Configuration File

Spring Boot configuration file application.yml example:

server:
  port: 8080

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/mydb
    username: root
    password: your_password

FAQ

Out of Memory

Increase JVM heap memory:

java21 -Xms1g -Xmx2g -jar app.jar

Port Conflict

Modify startup port:

java21 -jar app.jar --server.port=8081

Slow Startup

Check if there are external dependency connection timeouts, or limit JIT compilation to the first tier to speed up startup:

java21 -XX:TieredStopAtLevel=1 -jar app.jar

Avoid the legacy -noverify flag. It is deprecated and prints a warning on the modern Corretto builds AcePanel installs (e.g. Corretto 21). Prefer Application Class Data Sharing (-XX:+AutoCreateSharedArchive -XX:SharedArchiveFile=app.jsa) if you need faster cold starts.