package org.eweb4j.orm.dao.cascade;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.persistence.OneToMany;
import org.eweb4j.orm.config.ORMConfigBeanUtil;
import org.eweb4j.orm.dao.DAOException;
import org.eweb4j.orm.dao.DAOFactory;
import org.eweb4j.orm.sql.InsertSqlCreator;
import org.eweb4j.util.ReflectUtil;
/**
*
* @author weiwei
*
*/
public class OneToManyDAO {
private String dsName;
private Object t;
private List<Field> fields;
private ReflectUtil ru;
private String idField;
private String idVal;
private Method idGetter;
public OneToManyDAO(String dsName) {
this.dsName = dsName;
}
/**
* 初始化
*
* @param t
* @param fields
* @throws DAOException
*/
public void init(Object t, List<Field> fields) throws DAOException {
this.t = t;
this.fields = fields;
this.ru = new ReflectUtil(this.t);
// 主类的ID属性名
this.idField = ORMConfigBeanUtil.getIdField(this.t.getClass());
this.idGetter = ru.getGetter(idField);
if (idGetter == null)
throw new DAOException("can not find idGetter.", null);
Object idVal = null;
try {
idVal = idGetter.invoke(this.t);
this.idVal = idVal == null ? null : String.valueOf(idVal);
} catch (Exception e) {
throw new DAOException(idGetter + " invoke exception ", e);
}
}
/**
* 一对多（主从）级联插入 1.获取ID 2.插入次对象
*/
public void insert() throws DAOException {
if (this.fields == null || this.fields.size() == 0)
return;
if (idVal == null || "0".equals(idVal) || "".equals(idVal))
return;
else if (DAOFactory.getSelectDAO(dsName).selectOne(t, this.idField) == null)
return;
for (Field f : fields) {
String name = f.getName();
Method tarGetter = ru.getGetter(name);
if (tarGetter == null)
return;
OneToMany ann = tarGetter.getAnnotation(OneToMany.class);
if (ann == null) {
ann = f.getAnnotation(OneToMany.class);
if (ann == null)
continue;
}
List<?> tarList = null;
try {
tarList = (List<?>) tarGetter.invoke(t);
} catch (Exception e) {
throw new DAOException(tarGetter + " invoke exception ", e);
}
if (tarList == null)
continue;
for (int i = 0; i < tarList.size(); i++) {
try {
String field = idField;
Method fieldGetter = ru.getGetter(field);
Object fieldObj = fieldGetter.invoke(t);
String fieldVal = null;
if (fieldObj != null)
fieldVal = String.valueOf(fieldObj);
Object tarObj = tarList.get(i);
if (tarObj == null)
continue;
String tarRelColumn = ann.mappedBy();
if (tarRelColumn == null)
continue;
String tarIdColumn = ORMConfigBeanUtil.getIdColumn(tarObj
.getClass());
String[] columns = ORMConfigBeanUtil.getColumns(tarObj
.getClass());
List<String> colList = new ArrayList<String>(
Arrays.asList(columns));
int idIndex = colList.indexOf(tarIdColumn);
if (idIndex > -1)
colList.remove(idIndex);
int index = 0;
if (colList.contains(tarRelColumn)) {
index = colList.indexOf(tarRelColumn);
colList.set(index, tarRelColumn);
} else {
colList.add(tarRelColumn);
}
String[] values = ORMConfigBeanUtil.getValues(tarObj);
List<String> valList = new ArrayList<String>(
Arrays.asList(values));
if (idIndex > -1)
valList.remove(idIndex);
if (index > 0) {
valList.set(index, fieldVal);
} else {
valList.add(fieldVal);
}
String table = ORMConfigBeanUtil
.getTable(tarObj.getClass());
String[] tarColumns = colList.toArray(new String[] {});
String[] tarValues = valList.toArray(new String[] {});
String sql = InsertSqlCreator.createByColumnsIsValues(
table, tarColumns, tarValues);
if (sql != null)
// 将次对象一个一个插入到数据库
DAOFactory.getUpdateDAO(dsName).updateBySQL(sql);
} catch (Exception e) {
continue;
}
}
}
}
/**
* 一对多（主从）级联删除 1.前提条件必须主对象要存在于数据库中
* 2.检查当前主对象中的关联对象，如果关联对象为空，则删除所有与主对象有关的关联关系。
* 3.如果当前主对象中含有关联对象，则删除这些关联对象与主对象的关系
*/
public void delete() throws DAOException {
if (this.fields == null || this.fields.size() == 0)
return;
if (idVal == null || "0".equals(idVal) || "".equals(idVal))
return;
else if (DAOFactory.getSelectDAO(dsName).selectOne(t, this.idField) == null)
return;
for (Field f : fields) {
Method tarGetter = ru.getGetter(f.getName());
if (tarGetter == null)
continue;
OneToMany ann = tarGetter.getAnnotation(OneToMany.class);
if (ann == null) {
ann = f.getAnnotation(OneToMany.class);
if (ann == null)
continue;
}
Class<?> tarClass = ann.targetEntity();
String tarTable = ORMConfigBeanUtil.getTable(tarClass);
String column = ann.mappedBy();
List<?> tarList = null;
try {
tarList = (List<?>) tarGetter.invoke(t);
} catch (Exception e) {
throw new DAOException(tarGetter + " invoke exception ", e);
}
if (tarList == null || tarList.size() == 0) {
// 当关联对象为空的时候，删除所有关联对象
// delete from {tarTable} where {column} = {idVal}
String format = "delete from %s where %s = ? ";
String sql = String.format(format, tarTable, column);
DAOFactory.getUpdateDAO(dsName).updateBySQLWithArgs(sql, idVal);
} else {
for (int i = 0; i < tarList.size(); i++) {
Object tarObj = tarList.get(i);
if (tarObj == null)
continue;
// 检查是否该对象真的与主对象有关联且存在数据库
// select * from {tarTable} where {tarIdColumn} =
// {tarIdVal} and {column} = {idVal}
String format = "select * from %s where %s = ? and %s = ? ";
ReflectUtil tarRu = new ReflectUtil(tarObj);
String tarIdColumn = ORMConfigBeanUtil
.getIdColumn(tarClass);
String tarIdField = ORMConfigBeanUtil.getIdField(tarClass);
Method tarIdGetter = tarRu.getGetter(tarIdField);
if (tarIdGetter == null)
throw new DAOException("can not find tarIdGetter.",
null);
Object tarIdValObj = null;
try {
tarIdValObj = tarIdGetter.invoke(tarObj);
} catch (Exception e) {
throw new DAOException(tarIdGetter
+ " invoke exception ", e);
}
if (tarIdValObj == null)
continue;
String tarIdVal = String.valueOf(tarIdValObj);
if ("0".equals(tarIdVal) || "".equals(tarIdVal))
continue;
String sql = String.format(format, tarTable, tarIdColumn,
column);
boolean canDel = DAOFactory.getSelectDAO(dsName)
.selectBySQL(tarClass, sql, tarIdVal, idVal) == null ? false
: true;
if (canDel)
DAOFactory.getDeleteDAO(dsName).deleteById(tarObj);
}
}
}
}
/**
* 一对多（主从）级联查询
*/
public void select() throws DAOException {
if (this.fields == null || this.fields.size() == 0)
return;
if (idVal == null || "0".equals(idVal) || "".equals(idVal))
return;
else if (DAOFactory.getSelectDAO(dsName).selectOne(t, this.idField) == null)
return;
// select * from {tarTable} where {rel} = {idVal}
String format = "select * from %s where %s = ? ";
for (Field f : fields) {
Method tarGetter = ru.getGetter(f.getName());
if (tarGetter == null)
continue;
OneToMany ann = tarGetter.getAnnotation(OneToMany.class);
if (ann == null) {
ann = f.getAnnotation(OneToMany.class);
if (ann == null)
continue;
}
Class<?> tarClass = ann.targetEntity();
String tarTable = ORMConfigBeanUtil.getTable(tarClass);
String rel = ann.mappedBy();
String sql = String.format(format, tarTable, rel);
List<?> tarList = DAOFactory.getSelectDAO(dsName).selectBySQL(
tarClass, sql, idVal);
if (tarList == null)
continue;
Method tarSetter = ru.getSetter(f.getName());
if (tarSetter == null)
continue;
try {
tarSetter.invoke(t, tarList);
} catch (Exception e) {
throw new DAOException("", e);
}
}
}
}