/*** 實(shí)體對(duì)象的反射操作*/ public class EntityOperation<T> {private Logger log = Logger.getLogger(EntityOperation.class);public Class<T> entityClass = null; // 泛型實(shí)體Class對(duì)象public final Map<String, PropertyMapping> mappings;public final RowMapper<T> rowMapper;public final String tableName;public String allColumn = "*";public Field pkField;public EntityOperation(Class<T> clazz,String pk) throws Exception{if(!clazz.isAnnotationPresent(Entity.class)){throw new Exception("在" + clazz.getName() + "中沒有找到Entity注解，不能做ORM映射");}this.entityClass = clazz;Table table = entityClass.getAnnotation(Table.class);if (table != null) {this.tableName = table.name();} else {this.tableName = entityClass.getSimpleName();}Map<String, Method> getters = ClassMappings.findPublicGetters(entityClass);Map<String, Method> setters = ClassMappings.findPublicSetters(entityClass);Field[] fields = ClassMappings.findFields(entityClass);fillPkFieldAndAllColumn(pk,fields);this.mappings = getPropertyMappings(getters, setters, fields);this.allColumn = this.mappings.keySet().toString().replace("[", "").replace("]","").replaceAll(" ","");this.rowMapper = createRowMapper();}Map<String, PropertyMapping> getPropertyMappings(Map<String, Method> getters, Map<String, Method> setters, Field[] fields) {Map<String, PropertyMapping> mappings = new HashMap<String, PropertyMapping>();String name;for (Field field : fields) {if (field.isAnnotationPresent(Transient.class))continue;name = field.getName();if(name.startsWith("is")){name = name.substring(2);}name = Character.toLowerCase(name.charAt(0)) + name.substring(1);Method setter = setters.get(name);Method getter = getters.get(name);if (setter == null || getter == null){continue;}Column column = field.getAnnotation(Column.class);if (column == null) {mappings.put(field.getName(), new PropertyMapping(getter, setter, field));} else {mappings.put(column.name(), new PropertyMapping(getter, setter, field));}}return mappings;}RowMapper<T> createRowMapper() {return new RowMapper<T>() {public T mapRow(ResultSet rs, int rowNum) throws SQLException {try {T t = entityClass.newInstance();ResultSetMetaData meta = rs.getMetaData();int columns = meta.getColumnCount();String columnName;for (int i = 1; i <= columns; i++) {Object value = rs.getObject(i);columnName = meta.getColumnName(i);fillBeanFieldValue(t,columnName,value);}return t;}catch (Exception e) {throw new RuntimeException(e);}}};}protected void fillBeanFieldValue(T t, String columnName, Object value) {if (value != null) {PropertyMapping pm = mappings.get(columnName);if (pm != null) {try {pm.set(t, value);} catch (Exception e) {e.printStackTrace();}}}}private void fillPkFieldAndAllColumn(String pk, Field[] fields) {//設(shè)定主鍵try {if(!StringUtils.isEmpty(pk)){pkField = entityClass.getDeclaredField(pk);pkField.setAccessible(true);}} catch (Exception e) {log.debug("沒找到主鍵列,主鍵列名必須與屬性名相同");}for (int i = 0 ; i < fields.length ;i ++) {Field f = fields[i];if(StringUtils.isEmpty(pk)){Id id = f.getAnnotation(Id.class);if(id != null){pkField = f;break;}}}}public T parse(ResultSet rs) {T t = null;if (null == rs) {return null;}Object value = null;try {t = (T) entityClass.newInstance();for (String columnName : mappings.keySet()) {try {value = rs.getObject(columnName);} catch (Exception e) {e.printStackTrace();}fillBeanFieldValue(t,columnName,value);}} catch (Exception ex) {ex.printStackTrace();}return t;}public Map<String, Object> parse(T t) {Map<String, Object> _map = new TreeMap<String, Object>();try {for (String columnName : mappings.keySet()) {Object value = mappings.get(columnName).getter.invoke(t);if (value == null)continue;_map.put(columnName, value);}} catch (Exception e) {e.printStackTrace();}return _map;}public void println(T t) {try {for (String columnName : mappings.keySet()) {Object value = mappings.get(columnName).getter.invoke(t);if (value == null)continue;System.out.println(columnName + " = " + value);}} catch (Exception e) {e.printStackTrace();}} }class PropertyMapping {final boolean insertable;final boolean updatable;final String columnName;final boolean id;final Method getter;final Method setter;final Class enumClass;final String fieldName;public PropertyMapping(Method getter, Method setter, Field field) {this.getter = getter;this.setter = setter;this.enumClass = getter.getReturnType().isEnum() ? getter.getReturnType() : null;Column column = field.getAnnotation(Column.class);this.insertable = column == null || column.insertable();this.updatable = column == null || column.updatable();this.columnName = column == null ? ClassMappings.getGetterName(getter) : ("".equals(column.name()) ? ClassMappings.getGetterName(getter) : column.name());this.id = field.isAnnotationPresent(Id.class);this.fieldName = field.getName();}@SuppressWarnings("unchecked")Object get(Object target) throws Exception {Object r = getter.invoke(target);return enumClass == null ? r : Enum.valueOf(enumClass, (String) r);}@SuppressWarnings("unchecked")void set(Object target, Object value) throws Exception {if (enumClass != null && value != null) {value = Enum.valueOf(enumClass, (String) value);}//BeanUtils.setProperty(target, fieldName, value);try {if(value != null){setter.invoke(target, setter.getParameterTypes()[0].cast(value));}} catch (Exception e) {e.printStackTrace();/*** 出錯(cuò)原因如果是boolean字段 mysql字段類型 設(shè)置tinyint(1)*/System.err.println(fieldName + "--" + value);}} }

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