瞬态关键字可以标记方法吗？ [英] Can transient keywords mark a method?

问题描述

在java类java.util.Locale中，我发现关键字transient标记了一个方法。

In a java class java.util.Locale, I find that the keyword transient marked a method.

 public final class Locale
    implements Cloneable, Serializable
{
    private static class LocaleNameGetter
        implements sun.util.LocaleServiceProviderPool.LocalizedObjectGetter
    {

        public transient String getObject(LocaleNameProvider localenameprovider, Locale locale, String s, Object aobj[])
        {
            if(!$assertionsDisabled && aobj.length != 2)
                throw new AssertionError();
            int i = ((Integer)aobj[0]).intValue();
            String s1 = (String)aobj[1];
            switch(i)
            {
            case 0: // '\0'
                return localenameprovider.getDisplayLanguage(s1, locale);

            case 1: // '\001'
                return localenameprovider.getDisplayCountry(s1, locale);

            case 2: // '\002'
                return localenameprovider.getDisplayVariant(s1, locale);
            }
            if(!$assertionsDisabled)
                throw new AssertionError();
            else
                return null;
        }

有人可以告诉我为什么会这样吗？

Can someone tell me why can this be?

推荐答案

不，它不能，它只对字段有效。您似乎通过反编译从.class获取源代码。这是反编译器的错误，如果你看一下 java.lang.reflect.Modifier src，你会看到 transient 和 varargs 具有相同的值

No it can't, it's only valid for fields. You seem to get your source from .class by decompiling. This is the decompiler bug, if you take a look at java.lang.reflect.Modifier src you will see that transient and varargs have the same value

public static final int TRANSIENT        = 0x00000080;
...
static final int VARARGS   = 0x00000080;

字段 0x00000080 表示 transient ，对于方法（您的情况），它意味着 varargs 。这就是 getObject 在java.util.Locale src中的样子

for a field 0x00000080 means transient, for a method (your case) it means varargs. This is how getObject looks like in java.util.Locale src

public String getObject(LocaleNameProvider localeNameProvider,
                        Locale locale, 
                        String key,
                        Object... params) {   <-- varargs

在.class（字节码）中，varargs由Object []表示为最后一个参数+修饰符bit 7 = 1（0x80）。我想反编译器是旧的，根本不知道 varargs 这是自Java 1.5以来所以它打印为 transient 。

In .class (bytecode) varargs is represented by Object[] as the last parameter + modifier bit 7 = 1 (0x80). I guess the decompiler is old and simply does not know about varargs which is since Java 1.5 so it printed it as transient.

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