/**
* 为数据表自动增减字段
*
* @param dao Dao实例
* @param klass 映射Pojo
* @param add 是否允许添加
* @param del 是否允许删除
* @param tableName 动态表名上下文
*/
public static void migration(
Dao dao, final Class<?> klass, final boolean add, final boolean del, Object tableName) {
final AbstractJdbcExpert expert = (AbstractJdbcExpert) ((NutDao) dao).getJdbcExpert();
if (tableName != null && Strings.isNotBlank(tableName.toString())) {
dao = ext(dao, tableName);
}
final Entity<?> en = dao.getEntity(klass);
if (!dao.exists(klass)) return;
final List<Sql> sqls = new ArrayList<Sql>();
final Set<String> _indexs = new HashSet<String>();
final boolean sqlAddNeedColumn = !dao.meta().isOracle();
final boolean isCanComment = dao.meta().isMySql();
dao.run(
new ConnCallback() {
public void invoke(Connection conn) throws Exception {
expert.setupEntityField(conn, en);
Statement stat = null;
ResultSet rs = null;
ResultSetMetaData meta = null;
try {
// 获取数据库元信息
stat = conn.createStatement();
rs = stat.executeQuery("select * from " + en.getTableName() + " where 1 != 1");
meta = rs.getMetaData();
Set<String> columnNames = new HashSet<String>();
int columnCount = meta.getColumnCount();
for (int i = 1; i <= columnCount; i++) {
columnNames.add(meta.getColumnName(i).toLowerCase());
}
for (MappingField mf : en.getMappingFields()) {
if (mf.isReadonly()) continue;
String colName = mf.getColumnName();
if (columnNames.contains(colName.toLowerCase())) {
columnNames.remove(colName.toLowerCase());
continue;
}
if (add) {
log.infof("add column[%s] to table[%s]", mf.getColumnName(), en.getTableName());
StringBuilder sb = new StringBuilder("ALTER TABLE ");
sb.append(meta.getTableName(1)).append(" ADD ");
if (sqlAddNeedColumn) sb.append("COLUMN ");
sb.append(colName).append(" ").append(expert.evalFieldType(mf));
if (mf.isUnsigned()) {
sb.append(" UNSIGNED");
}
if (mf.isNotNull()) {
sb.append(" NOT NULL");
}
if (mf.getColumnType() == ColType.TIMESTAMP) {
if (mf.hasDefaultValue()) {
sb.append(" ").append(mf.getDefaultValue(null).replaceAll("@", "@@"));
} else {
if (mf.isNotNull()) {
sb.append(" DEFAULT 0");
} else {
sb.append(" NULL DEFAULT NULL");
}
}
} else {
if (mf.hasDefaultValue()) expert.addDefaultValue(sb, mf);
}
if (mf.hasColumnComment() && isCanComment) {
sb.append(" COMMENT '").append(mf.getColumnComment()).append("'");
}
sb.append(';');
Sql sql = Sqls.create(sb.toString());
sqls.add(sql);
}
}
if (del) {
for (String colName : columnNames) {
log.infof("del column[%s] from table[%s]", colName, en.getTableName());
Sql sql = Sqls.create("ALTER table $table DROP column $name");
sql.vars().set("table", en.getTableName());
sql.vars().set("name", colName);
sqls.add(sql);
}
}
// show index from mytable;
String showIndexs = "show index from " + en.getTableName();
PreparedStatement ppstat = conn.prepareStatement(showIndexs);
ResultSet rest = ppstat.executeQuery();
while (rest.next()) {
String index = rest.getString(3);
_indexs.add(index);
}
} catch (SQLException e) {
if (log.isDebugEnabled())
log.debugf("migration Table '%s' fail!", en.getTableName(), e);
}
// Close ResultSet and Statement
finally {
Daos.safeClose(stat, rs);
}
}
});
for (Sql sql : sqls) {
dao.execute(sql);
}
// 创建索引
List<Sql> indexsSql = createIndexs(dao, en, _indexs, tableName);
if (!Lang.isEmpty(indexsSql)) {
dao.execute(indexsSql.toArray(new Sql[0]));
}
// 创建关联表
expert.createRelation(dao, en);
}
