第三章
请说明resource注解和Autowired区别
可以参考这篇文章
@Autowired和@Resource的区别
beanUtils
源码
private static void copyProperties(Object source, Object target, @Nullable Class<?> editable, @Nullable String... ignoreProperties) throws BeansException {
Assert.notNull(source, "Source must not be null");
Assert.notNull(target, "Target must not be null");
Class<?> actualEditable = target.getClass();
if (editable != null) {
if (!editable.isInstance(target)) {
throw new IllegalArgumentException("Target class [" + target.getClass().getName() + "] not assignable to Editable class [" + editable.getName() + "]");
}
actualEditable = editable;
}
//获取属性描述符
PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);
//无需copy的属性
List<String> ignoreList = ignoreProperties != null ? Arrays.asList(ignoreProperties) : null;
PropertyDescriptor[] var7 = targetPds;
int var8 = targetPds.length;
for(int var9 = 0; var9 < var8; ++var9) {
PropertyDescriptor targetPd = var7[var9];
//获取目标类的写方法
Method writeMethod = targetPd.getWriteMethod();
if (writeMethod != null && (ignoreList == null || !ignoreList.contains(targetPd.getName()))) {
//从source的get拿到值set到target中
PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(), targetPd.getName());
if (sourcePd != null) {
Method readMethod = sourcePd.getReadMethod();
if (readMethod != null) {
ResolvableType sourceResolvableType = ResolvableType.forMethodReturnType(readMethod);
ResolvableType targetResolvableType = ResolvableType.forMethodParameter(writeMethod, 0);
if (targetResolvableType.isAssignableFrom(sourceResolvableType)) {
try {
if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
readMethod.setAccessible(true);
}
Object value = readMethod.invoke(source);
if (!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers())) {
writeMethod.setAccessible(true);
}
writeMethod.invoke(target, value);
} catch (Throwable var17) {
throw new FatalBeanException("Could not copy property '" + targetPd.getName() + "' from source to target", var17);
}
}
}
}
}
}
}