阿里云ECS多版本JDK切换

步骤 1：更新系统并安装基础工具

复制代码

sudo dnf update -y
sudo dnf install -y wget tar

步骤 2：安装 JDK 8、11、17（通过默认仓库）

复制代码

# JDK 8
sudo dnf install -y java-1.8.0-openjdk-devel

# JDK 11
sudo dnf install -y java-11-openjdk-devel

# JDK 17
sudo dnf install -y java-17-openjdk-devel

# JDK 21
sudo dnf install -y java-21-openjdk-devel

验证 JDK 安装

复制代码

# 检查所有 JDK
ls /usr/lib/jvm/

# 应该看到：
# java-1.8.0-openjdk-1.8.0.372
# java-11-openjdk-11.0.19
# java-17-openjdk-17.0.10
# java-21-openjdk-21.0.2

配置多 JDK 版本管理（使用 alternatives）

复制代码

# 1. 注册 JDK 8
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.372/bin/java 8

# 2. 注册 JDK 11
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-11-openjdk-11.0.19/bin/java 11

# 3. 注册 JDK 17
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-17-openjdk-17.0.10/bin/java 17

# 4. 注册 JDK 21
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-21-openjdk-21.0.2/bin/java 21

# 5. 切换版本
sudo alternatives --config java

✅ 执行后，系统会显示版本列表，输入对应数字即可切换

完整 JDK 版本对照表

JDK 版本	包名	安装命令	路径
JDK 8	`java-1.8.0-openjdk-devel`	`sudo dnf install -y java-1.8.0-openjdk-devel`	`/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.372/bin/java`
JDK 11	`java-11-openjdk-devel`	`sudo dnf install -y java-11-openjdk-devel`	`/usr/lib/jvm/java-11-openjdk-11.0.19/bin/java`
JDK 17	`java-17-openjdk-devel`	`sudo dnf install -y java-17-openjdk-devel`	`/usr/lib/jvm/java-17-openjdk-17.0.10/bin/java`
JDK 21	`java-21-openjdk-devel`	`sudo dnf install -y java-21-openjdk-devel`	`/usr/lib/jvm/java-21-openjdk-21.0.2/bin/java`

一键安装脚本（完整版）

复制代码

#!/bin/bash
# Alibaba Cloud Linux 3 JDK 8/11/17/21 安装脚本

# 1. 更新系统
sudo dnf update -y

# 2. 安装基础工具
sudo dnf install -y wget tar

# 3. 添加 Adoptium 仓库
sudo dnf install -y https://packages.adoptium.net/artifactory/deb/$(lsb_release -cs)/pool/main/a/adoptium-java/adoptium-java-21_21.0.2.0-1-1_all.deb

# 4. 安装 JDK 8, 11, 17, 21
sudo dnf install -y java-1.8.0-openjdk-devel java-11-openjdk-devel java-17-openjdk-devel java-21-openjdk-devel

# 5. 注册到 alternatives
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.372/bin/java 8
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-11-openjdk-11.0.19/bin/java 11
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-17-openjdk-17.0.10/bin/java 17
sudo alternatives --install /usr/bin/java java /usr/lib/jvm/java-21-openjdk-21.0.2/bin/java 21

# 6. 创建项目级切换脚本
echo '#!/bin/bash
jdk=$(cat .java-version)
case "$jdk" in
    8)
        sudo alternatives --set java /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.372/bin/java
        ;;
    11)
        sudo alternatives --set java /usr/lib/jvm/java-11-openjdk-11.0.19/bin/java
        ;;
    17)
        sudo alternatives --set java /usr/lib/jvm/java-17-openjdk-17.0.10/bin/java
        ;;
    21)
        sudo alternatives --set java /usr/lib/jvm/java-21-openjdk-21.0.2/bin/java
        ;;
    *)
        echo "错误：不支持的 JDK 版本 $jdk"
        exit 1
        ;;
esac
echo "✅ 已切换到 JDK $jdk"' > usejdk.sh
chmod +x usejdk.sh

echo "✅ JDK 8/11/17/21 安装完成！
- 项目级切换：在项目根目录创建 .java-version 文件（如 '21'）
- 使用：./usejdk.sh"

📌 执行方式：
复制代码
chmod +x install_jdk.sh
./install_jdk.sh