BaseProvider.java 文件源码

/**
 * queryByPrimaryKey
 *
 * @param obj 实体bean
 * @return sql
 */
public String queryByPrimaryKey(Object obj) {
    Table table = getTable(obj);
    String key = "queryByPrimaryKey_" + table.getClass();
    String sql = sqlMap.get(key);
    if (sql == null) {
        StringBuilder stringBuilder = new StringBuilder("select ");
        StringBuilder columnStr = new StringBuilder();
        Map<String, String> columnMap = columnMap(obj.getClass());
        for (Map.Entry<String, String> entry : columnMap.entrySet()) {
            columnStr.append(entry.getKey());
            columnStr.append(" as ");
            columnStr.append(entry.getValue());
            columnStr.append(" ,");
        }
        columnStr.deleteCharAt(columnStr.lastIndexOf(","));
        stringBuilder.append(columnStr.toString());
        stringBuilder.append(" from ");
        stringBuilder.append(table.name());
        stringBuilder.append(buildWhereByPrimaryKey(obj.getClass()));
        sql = stringBuilder.toString();
        sqlMap.put(key, sql);

    }
    return sql;
}