我正在使用松露& Graal項目在我自己的項目中。我遇到了一個問題,即當我在Java中使用getDeclaredField()
時,即使該字段存在,也會返回noSuchFieldException。getDeclaredField即使字段存在也會返回nosuchfield異常
的碼產生的例外是
Field field = NodeUtil.class.getDeclaredField("unsafeFieldOffsetProvider");
field.setAccessible(true);
而字段unsafeFieldOffsetProvider
在NodeUtil.java被聲明
private static final FieldOffsetProvider unsafeFieldOffsetProvider = new FieldOffsetProvider() {
@Override
public long objectFieldOffset(Field field) {
return unsafe.objectFieldOffset(field);
}
@Override
public int getTypeSize(Class<?> clazz) {
if (!clazz.isPrimitive()) {
return Unsafe.ARRAY_OBJECT_INDEX_SCALE;
} else if (clazz == int.class) {
return Unsafe.ARRAY_INT_INDEX_SCALE;
} else {
throw new UnsupportedOperationException("unsupported field type: " + clazz);
}
}
};
下面是錯誤消息:
Exception in thread "main" java.lang.ExceptionInInitializerError
at edu.uci.python.runtime.object.FixedObjectLayout.<init>(FixedObjectLayout.java:100)
at edu.uci.python.runtime.object.FixedObjectLayout.addAttribute(FixedObjectLayout.java:149)
at edu.uci.python.runtime.object.PythonObject.setAttribute(PythonObject.java:153)
at edu.uci.python.runtime.standardtype.PythonModule.addDefaultConstants(PythonModule.java:45)
at edu.uci.python.runtime.standardtype.PythonModule.<init>(PythonModule.java:41)
at edu.uci.python.builtins.PythonDefaultBuiltinsLookup.createModule(PythonDefaultBuiltinsLookup.java:88)
at edu.uci.python.builtins.PythonDefaultBuiltinsLookup.populateBuiltins(PythonDefaultBuiltinsLookup.java:54)
at edu.uci.python.runtime.PythonContext.<init>(PythonContext.java:79)
at python.truffle.toa.runtime.PythonContextOA.<init>(PythonContextOA.java:13)
at python.truffle.toa.main.PythonMainOA.testFile(PythonMainOA.java:78)
at python.truffle.toa.main.PythonMainOA.main(PythonMainOA.java:39)
Caused by: java.lang.RuntimeException: java.lang.NoSuchFieldException: unsafeFieldOffsetProvider
at edu.uci.python.runtime.object.ObjectLayoutUtil.unsafeFieldOffsetProvider(ObjectLayoutUtil.java:43)
at edu.uci.python.runtime.object.ObjectLayoutUtil.<clinit>(ObjectLayoutUtil.java:47)
... 11 more
Caused by: java.lang.NoSuchFieldException: unsafeFieldOffsetProvider
at java.lang.Class.getDeclaredField(Unknown Source)
at edu.uci.python.runtime.object.ObjectLayoutUtil.unsafeFieldOffsetProvider(ObjectLayoutUtil.java:39)
... 12 more
如果該字段確實在您引用的類中聲明,則不會發生。 [例子](http://ideone.com/uOOini)很明顯,它不應該真的屬於這個類;也許源文件和'.class'文件不同步?也許你正在引用一個*不同的''NodeUtil'類? –
是的,就是這一點。我會仔細檢查構建路徑和項目資源。 – lhan
我不知道這個Truffle&Graal項目非常好。但它是否會爲您的節點創建代理對象? – bvdb