Java Error: Java11 New Security Option Error, How to Handle and Avoid

Java is a programming language widely used for developing applications. With the introduction of Java 11, new security options have been introduced. However, these new options may also cause some problems. This article will discuss the new security options errors in Java11 and how to deal with them and avoid them.

New security options

The new security options in Java11 mainly involve the following three aspects:

1. Application class loader

Java11 introduces a new application class loader and introduces some new options to control the behavior of the application class loader. These options mainly include:

• The Xshare:off option is used to turn off the shared class caching function.
• --class-path option is used to specify the class path that the application needs to load.
• --module-path option is used to specify the module path that the application needs to load.

2. Disable default algorithms

Some unsafe encryption algorithms, such as SHA-1 and MD5, are disabled by default in Java11. In order to enable these algorithms, special options are required. These options include:

• --add-exports The java.base/jdk.internal.crypto=ALL-UNNAMED option exposes cryptographic functionality to unnamed modules.
• --add-opens java.base/java.security=ALL-UNNAMED option is used to open the Java security directory to unnamed modules.

3. Compiler Limitations

Java11 also introduces some new compiler limitations. These restrictions mainly apply to the following situations:

• Access to classes in the sun.misc package is prohibited.
• The use of certain Java SE APIs is prohibited.
• Using unpublished APIs is prohibited.

Java11 New Security Option Error

When upgrading to Java11, application developers may encounter the following errors:

1. java. lang.IllegalAccessException exception

When accessing the sun.misc.Unsafe class through reflection, a java.lang.IllegalAccessException exception may occur. This is because Java11 no longer allows access to classes in the sun.misc package.

Solution: Replace the Unsafe class with safe methods. For example, use java.nio.Bits or java.lang.invoke.VarHandle.

2. java.lang.NoClassDefFoundError exception

The java.lang.NoClassDefFoundError exception may occur when an application uses the application class loader to load a class. This is usually caused by enabling the -Xshare:off option, which turns off shared class caching.

Workaround: Use the following command line option to enable shared class caching:

java -Xshare:auto -jar app.jar

3. Compilation error

When an application attempts to use the Java SE API or undocumented APIs, it may encounter compilation errors.

Solution: Use alternative APIs in the Java standard library or implement the functionality yourself. At the same time, avoid using unauthorized APIs.

Avoid Java11 new security option errors

In addition to the above solutions, there are some following methods to help avoid Java11 new security option errors:

1. Upgrade the application

Upgrade your applications whenever possible to adapt to Java 11’s new security options. If an application is using an outdated API, then the application will encounter more problems.

2. Understand the new security options

Understand the new security options in Java11 and learn how to use them correctly.

3. Use new options

Use new options in Java 11 to control application and class loader behavior.

4. Test the application

Test the application to ensure it runs in the new Java11 environment and handles the new security options correctly.

Conclusion

Java11’s new security options can make Java applications more secure. However, these options may also cause some problems. Understanding and using these options correctly, as well as testing your application, can help avoid these problems. If problems are encountered, we need to take timely steps to resolve them to ensure the smooth running of the application.

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