| java.lang.Object | ||||
|---|---|---|---|---|
| ↳ | java.lang.Throwable | |||
| ↳ | java.lang.Error | |||
| ↳ | java.lang.LinkageError | |||
| ↳ | java.lang.ExceptionInInitializerError |
ExceptionInInitializerError 通常意味着在静态初始化块或静态变量初始化过程中发生了异常。
静态代码块异常：如果在静态代码块中有任何异常抛出，都会导致此错误。
public class StaticBlock {
private static int state;
static {
state = 42 / 0; //除0异常
}
}
静态变量初始化异常：如果静态变量在初始化时抛出了异常，也会导致此错误。（编译后实际上也是在静态代码块里面）
public class Example {
private static final int number = Integer.parseInt("abc"); // 这里会抛出NumberFormatException
}
解决方法
一般来说，查看堆栈跟踪都能找出问题所在。
- 检查静态初始化块：确保静态初始化块中没有抛出异常的代码。
- 检查静态变量初始化：确保所有静态变量的初始化都是安全的，没有抛出异常。
工作中的例子
java.lang.ExceptionInInitializerError at com.xxx.xx.Service.onInit(Service.java:654)
查看654行代码，引用了一个静态类。
static {
try {
String path = "/data/data/com.xxx.xx/lib/libxxplay.so";
File file = new File(path);
if (file.exists()) {
SFLogger.d(TAG, "use /data/data/com.xxx.xx/lib/libxxplay.so");
System.load(path);
} else {
SFLogger.d(TAG, "use /system/lib/libxxplay.so");
System.loadLibrary("xxplay");
}
} catch (Exception e) {
SFLogger.e(TAG, "JniUtil loadLibrary exception = " + e.getMessage());
}
}
以上代码咋一看好像也没什么问题啊，异常都catch住了。
但如果仔细研究就会发现，这里的问题是滥用了Exception，没有针对具体异常进行捕获。查看loadLibrary源码发现其可能会抛出SecurityException、UnsatisfiedLinkError或者NullPointerException，SecurityException和NullPointerException的父类都是RuntimeException，是一种异常（Exception），UnsatisfiedLinkError的父类是LinkageError，是一种错误（Error），所以如果这里发生了UnsatisfiedLinkError，通过Exception是捕获不了的，必须通过他们的共同父类Throwable来进行捕获。当然，最好还是针对具体的异常进行捕获，不要用这种扩大化的捕获方式，容易隐藏问题。
/**
* Loads the native library specified by the <code>libname</code>
* argument. The <code>libname</code> argument must not contain any platform
* specific prefix, file extension or path. If a native library
* called <code>libname</code> is statically linked with the VM, then the
* JNI_OnLoad_<code>libname</code> function exported by the library is invoked.
* See the JNI Specification for more details.
*
* Otherwise, the libname argument is loaded from a system library
* location and mapped to a native library image in an implementation-
* dependent manner.
* <p>
* The call <code>System.loadLibrary(name)</code> is effectively
* equivalent to the call
* <blockquote><pre>
* Runtime.getRuntime().loadLibrary(name)
* </pre></blockquote>
*
* @param libname the name of the library.
* @exception SecurityException if a security manager exists and its
* <code>checkLink</code> method doesn't allow
* loading of the specified dynamic library
* @exception UnsatisfiedLinkError if either the libname argument
* contains a file path, the native library is not statically
* linked with the VM, or the library cannot be mapped to a
* native library image by the host system.
* @exception NullPointerException if <code>libname</code> is
* <code>null</code>
* @see java.lang.Runtime#loadLibrary(java.lang.String)
* @see java.lang.SecurityManager#checkLink(java.lang.String)
*/
@CallerSensitive
public static void loadLibrary(String libname) {
Runtime.getRuntime().loadLibrary0(Reflection.getCallerClass(), libname);
}
参考
ExceptionInInitializerError | Android Developers
When Does Java Throw the ExceptionInInitializerError? | Baeldung