java通过反射获取类名、属性名称以及@Table注解上的表名称

import javax.persistence.Column;
import javax.persistence.Id;
import javax.persistence.Table;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
* @author caizw
* @createDate 2018/2/8
* @description 反射工具类
*/
public class ReflectUtils {

/**
* 获取实体类主键
*
* @param clazz
* @return
*/
public static Field getIdField(Class<?> clazz) {
Field[] fields = clazz.getDeclaredFields();
Field item = null;
for (Field field : fields) {
Id id = field.getAnnotation(Id.class);
if (id != null) {
field.setAccessible(true);
item = field;
break;
}
}
if (item == null) {
Class<?> superclass = clazz.getSuperclass();
if (superclass != null) {
item = getIdField(superclass);
}
}
return item;
}

/**
* 根据主键名称获取实体类主键属性值
*
* @param clazz
* @param pkName
* @return
*/
public static Object getPkValueByName(Object clazz, String pkName) {
try {
String firstLetter = pkName.substring(0, 1).toUpperCase();
String getter = "get" + firstLetter + pkName.substring(1);
Method method = clazz.getClass().getMethod(getter, new Class[]{});
Object value = method.invoke(clazz, new Object[]{});
return value;
} catch (Exception e) {
return null;
}
}

/**
* 通过反射将 class1不为空的值赋值给class2
*
* @param class1
* @param class2
* @throws Exception
*/
public static void reflectClass1ToClass2(Object class1, Object class2) throws Exception {
Field[] field = class1.getClass().getDeclaredFields();
for (int i = 0; i < field.length; i++) {
String name = field[i].getName();
if ("serialVersionUID".equals(name)) {
continue;
}
name = name.substring(0, 1).toUpperCase() + name.substring(1);
Method m1 = class1.getClass().getMethod("get" + name);
Object value = m1.invoke(class1);
if (value != null) {
Field f = field[i];
f.setAccessible(true);
f
4000
.set(class2, value);
}
}
}

/**
* 获取实体类 @Column 的其中一个属性名称
*
* @param clazz
* @return
*/
public static Map<String, String> getColumnName(Class<?> clazz) {
Map<String, String> map = new ConcurrentHashMap<>();
Field[] fields = clazz.getDeclaredFields();
for (Field field : fields) {
if (field.isAnnotationPresent(Column.class)) {
/**
* 获取字段名
*/
Column declaredAnnotation = field.getDeclaredAnnotation(Column.class);
String column = declaredAnnotation.name();
map.put("fieldNames", field.getName());
map.put("column", column);
break;
}
}
return map;
}

/**
* 通过获取类上的@Table注解获取表名称
*
* @param clazz
* @return
*/
public static Map<String, String> getTableName(Class<?> clazz) {
Map<String, String> map = new ConcurrentHashMap<>();
Table annotation = clazz.getAnnotation(Table.class);
String name = annotation.name();
String className = clazz.getSimpleName();
map.put("tableName", name);
map.put("className", className);
return map;
}
}