Android ClassLoader源码

hint：源码基于android8.0 sdk版本：26

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ClassLoader#loadClass(java.lang.String)

protected Class<?> loadClass(String name, boolean resolve)
    throws ClassNotFoundException
{
        // First, check if the class has already been loaded
        Class<?> c = findLoadedClass(name);
        if (c == null) {
            try {
                if (parent != null) {
                    c = parent.loadClass(name, false);
                } else {
                    c = findBootstrapClassOrNull(name);
                }
            } catch (ClassNotFoundException e) {
                // ClassNotFoundException thrown if class not found
                // from the non-null parent class loader
            }

            if (c == null) {
                // If still not found, then invoke findClass in order
                // to find the class.
                c = findClass(name);
            }
        }
        return c;
}

子类BaseDexClassLoader

private final DexPathList pathList;

findClass

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DexPathList

private Element[] dexElements; 构造初始化

Element

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DexPathList--makeDexElements

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DexPathList--findClass

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Element--findClass

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DexPathList--loadDexFile

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DexFile

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DexFile--loadDex

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DexFile--loadClassBinaryName、defineClass、defineClassNative

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Android8.0+主角--PathClassLoader

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