Java FieldAccessor类代码示例

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private FieldAccessor acquireFieldAccessor(boolean overrideFinalCheck) {
    // First check to see if one has been created yet, and take it
    // if so
    FieldAccessor tmp = null;
    if (root != null) tmp = root.getFieldAccessor(overrideFinalCheck);
    if (tmp != null) {
        if (overrideFinalCheck)
            overrideFieldAccessor = tmp;
        else
            fieldAccessor = tmp;
    } else {
        // Otherwise fabricate one and propagate it up to the root
        tmp = reflectionFactory.newFieldAccessor(this, overrideFinalCheck);
        setFieldAccessor(tmp, overrideFinalCheck);
    }

    return tmp;
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
public static void setStaticFinalField(
        Field field, Object value)
        throws NoSuchFieldException, IllegalAccessException
{
    // 获得 public 权限
    field.setAccessible(true);
    // 将modifiers域设为非final,这样就可以修改了
    Field modifiersField =
            Field.class.getDeclaredField(MODIFIERS_FIELD);
    modifiersField.setAccessible(true);
    int modifiers = modifiersField.getInt(field);
    // 去掉 final 标志位
    modifiers &= ~Modifier.FINAL;
    modifiersField.setInt(field, modifiers);
    FieldAccessor fa = reflection.newFieldAccessor(
            field, false
    );
    fa.set(null, value);
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
public static void setFailsafeFieldValue(Field field, Object target, Object value)
        throws NoSuchFieldException, IllegalAccessException {

    // let's make the field accessible
    field.setAccessible(true);

    // next we change the modifier in the Field instance to
    // not be final anymore, thus tricking reflection into
    // letting us modify the static final field
    Field modifiersField = Field.class.getDeclaredField("modifiers");
    modifiersField.setAccessible(true);
    int modifiers = modifiersField.getInt(field);

    // blank out the final bit in the modifiers int
    modifiers &= ~Modifier.FINAL;
    modifiersField.setInt(field, modifiers);

    FieldAccessor fa = ReflectionFactory.getReflectionFactory().newFieldAccessor(field, false);
    fa.set(target, value);
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private FieldAccessor acquireFieldAccessor(boolean overrideFinalCheck) {
    // First check to see if one has been created yet, and take it
    // if so
    FieldAccessor tmp = null;
    if (root != null) tmp = root.getFieldAccessor(overrideFinalCheck);
    if (tmp != null) {
        if (overrideFinalCheck)
            overrideFieldAccessor = tmp;
        else
            fieldAccessor = tmp;
    } else {
        // Otherwise fabricate one and propagate it up to the root
        tmp = reflectionFactory.newFieldAccessor(this, overrideFinalCheck);
        setFieldAccessor(tmp, overrideFinalCheck);
    }
    return tmp;
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private static void setField(Field field, Object target, Object value) throws NoSuchFieldException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException {
    field.setAccessible(true);
    Field modifiersField = Field.class.getDeclaredField("modifiers");
    modifiersField.setAccessible(true);
    modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);

    FieldAccessor fieldAccessor = ReflectionFactory.getReflectionFactory().newFieldAccessor(field, true);
    fieldAccessor.set(target, value);
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private FieldAccessor getFieldAccessor(Object obj)
    throws IllegalAccessException
{
    boolean ov = override;
    FieldAccessor a = (ov) ? overrideFieldAccessor : fieldAccessor;
    return (a != null) ? a : acquireFieldAccessor(ov);
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private void setFieldAccessor(FieldAccessor accessor, boolean overrideFinalCheck) {
    if (overrideFinalCheck)
        overrideFieldAccessor = accessor;
    else
        fieldAccessor = accessor;
    // Propagate up
    if (root != null) {
        root.setFieldAccessor(accessor, overrideFinalCheck);
    }
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private static void setFailSafeFieldValue(Field field, Object target, Object value) throws NoSuchFieldException,
        IllegalAccessException {
    field.setAccessible(true);
    Field modifiersField = Field.class.getDeclaredField("modifiers");
    modifiersField.setAccessible(true);
    int modifiers = modifiersField.getInt(field);
    modifiers &= ~Modifier.FINAL;
    modifiersField.setInt(field, modifiers);
    FieldAccessor fa = reflectionFactory.newFieldAccessor(field, false);
    fa.set(target, value);
}
 

import sun.reflect.FieldAccessor; //导入依赖的package包/类
private FieldAccessor getFieldAccessor(Object obj)
    throws IllegalAccessException
{
    doSecurityCheck(obj);
    boolean ov = override;
    FieldAccessor a = (ov)? overrideFieldAccessor : fieldAccessor;
    return (a != null)? a : acquireFieldAccessor(ov);
}