Java 1.7 for Mac 还能用吗？-杰瑞科技汇

Of course. Here is a comprehensive guide to installing and using Java 1.7 on a Mac.

Important Warning: Why Java 1.7 is Extremely Outdated

Before you proceed, it's crucial to understand the risks associated with Java 1.7 (also known as Java 7).

No Security Updates: Oracle, the owner of Java, ended public updates for Java 1.7 in April 2025. This means it has zero security patches. Any computer running Java 1.7 is highly vulnerable to malware, viruses, and other exploits.
No Bug Fixes: All known bugs and performance issues will never be fixed.
Modern Applications Don't Support It: Virtually all modern software, web applications, and development tools require Java 8 or newer.

You should only use Java 1.7 if you are:

Maintaining a legacy application that is frozen and cannot be upgraded.
Working on an academic project that specifically requires Java 1.7 APIs for learning purposes.
Running a very old, specific piece of hardware or software that has no Java 1.8+ compatible version.

For any other purpose, please upgrade to a modern, supported version of Java (e.g., Java 11, 17, or 21).

How to Install Java 1.7 on a Mac

Apple stopped including Java with macOS starting with OS X 10.7 (Lion). Therefore, you must install it manually using an archive package from Oracle.

Step 1: Download the Java 1.7 Installer

You need to get the official installer from Oracle's archive. The direct links can sometimes change, but the process is to go to the Oracle Java Archive.

Go to the Oracle Java Archive page: https://www.oracle.com/java/technologies/javase/javase7-archive-downloads.html
You will need to accept the license agreement. Click the link for "JDK 7u80" (or the latest "u" update available in the archive, which is 80 as of this writing). This version is more stable and secure than earlier 7u releases.
On the download page, find the section for "Mac OS X x64".
Download the file named jdk-7u80-macosx-x64.dmg.

Step 2: Run the Installer

Once the download is complete, open your Downloads folder and double-click the .dmg file.
A window will appear with the JDK installer icon. Drag and drop this icon into your Applications folder.
Open your Applications folder and double-click the JDK 7 Update 80 icon to launch the installer.
Follow the on-screen instructions. You may need to enter your administrator password to complete the installation.

Step 3: Verify the Installation

After the installation is complete, you need to verify that it was successful and configure your system to use it.

Open the Terminal. You can find it in Applications/Utilities or by searching for it with Spotlight (Cmd+Space).
Check the Installed Version: Run the following command. This will check the version of the javac compiler (which comes with the JDK).
```
/usr/libexec/java_home -V
```
You should see output similar to this, showing that Java SE 7 is installed:
```
Matching Java Virtual Machines (2):
    1.7.0_80, x86_64:   "Java SE 7" /Library/Java/JavaVirtualMachines/jdk1.7.0_80.jdk/Contents/Home
    1.8.0_342, x86_64:  "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_342.jdk/Contents/Home
/Library/Java/JavaVirtualMachines/jdk1.8.0_342.jdk/Contents/Home
```
Notice that the default version is still Java 8. This is the safe and recommended behavior. We will now show you how to switch to Java 7 when you need it.

How to Switch Between Java Versions (macOS `java_home`)

The modern way to manage Java versions on a Mac is using the java_home utility and setting environment variables in your shell profile. This is the recommended method over manually editing system files.

Method 1: Temporarily Set the Java Version for the Current Terminal Session

This is useful if you just need to run a command or a script with Java 7 without changing your system's default.

Find the exact path to Java 1.7:
```
/usr/libexec/java_home -v 1.7
```
This will output the path, for example: /Library/Java/JavaVirtualMachines/jdk1.7.0_80.jdk/Contents/Home
Set the JAVA_HOME variable for your current session:
```
export JAVA_HOME=`/usr/libexec/java_home -v 1.7`
```
Verify that it's working:
```
echo $JAVA_HOME
```
And
```
java -version
```
The output should now show:
```
java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)
```
Remember: This change is only for the current Terminal window. If you close it and open a new one, it will revert to the default Java version.

Method 2: Permanently Set the Default Java Version (Not Recommended)

You can permanently set your default Java version by adding the export command to your shell's startup file.

Find your shell profile file. It's likely ~/.zshrc if you are on macOS Catalina (10.15) or newer, or ~/.bash_profile if you are on an older version. You can check by running echo $SHELL. If it says /bin/zsh, use .zshrc. If it says /bin/bash, use .bash_profile.
Edit the file:
```
open -e ~/.zshrc
```
(or open -e ~/.bash_profile)

Add the following line to the end of the file:

export JAVA_HOME=`/usr/libexec/java_home -v 1.7`

Save the file and close the editor.
Apply the changes by either restarting your Terminal or by running source ~/.zshrc (or source ~/.bash_profile).

Now, every new Terminal session will have Java 1.7 as the default. Remember to switch back to a modern version when you are done with your legacy work!

Alternative: Using SDKMAN! (Highly Recommended for Developers)

If you are a developer who frequently needs to switch between multiple Java versions, using a version manager like SDKMAN! is the best practice. It handles the installation and switching for you cleanly.

Install SDKMAN!:
```
curl -s "https://get.sdkman.io" | bash
```
Follow the on-screen instructions to complete the setup. You'll need to open a new terminal session afterwards.
Install Java 1.7 using SDKMAN!:
```
sdk install java 7.0.80-tem
```
(The tem stands for Temurin, a popular open-source build, but you can also use oracle if you prefer the official build).
Switch to Java 1.7:
```
sdk use java 7.0.80-tem
```
Switch back to a default (modern) version:
```
sdk default java 17.0.8-tem
```
This is much cleaner and less error-prone than manually editing configuration files.

Java 1.7 for Mac 还能用吗？

Important Warning: Why Java 1.7 is Extremely Outdated