java大作业:java实现数据库的底层实现

package com.jdbc.dataBase; import java.io.File; import java.util.ArrayList; import java.util.HashMap; import java.util.IdentityHashMap; import java.util.List; import java.util.Map; import java.util.Vector; import com.jdbc.JdbcBasicPro; import com.jdbc.JdbcDataUtil; /** * @ClassName: JdbcBasicImpl * @Description: 数据库的实现类，继承接口JdbcBasic * @author * @date */ public class JdbcBasicImpl{ /** * @Title: createTable * @Description: 建表的实现类 * @return void 返回类型 * @throws */ public void createTable(String tableName,Vector<String> tableHead,boolean flag) { String strTemp = ""; if(!JavaDataBaseUtil.isTable(tableName) || flag){ List<String> list = new ArrayList<String>(); String tablePath = JdbcDataUtil.dataPathCVS + tableName+".csv"; if (tableHead.size()==0) { System.out.println("error : 表头发生错误：JdbcBasicImpl.createTable(String tableName,Vector<String> tableHead)"); return; } for (int i = 0; i < tableHead.size(); i++) { if (i==0) { strTemp = JavaDataBaseUtil.getIdentity(tableHead.elementAt(0)); }else { strTemp += (","+JavaDataBaseUtil.getIdentity(tableHead.elementAt(i))); } } list.add(strTemp); JavaDataBaseUtil.getDataWrite(tablePath,list); }else{ System.out.println("error : 创建表发生错误，错误原因：已存在此表单【"+tableName+"】【JdbcBasicImpl.createTable(String tableName,Vector<String> tableHead)】"); return; } } /** * @Title: insertTable * @Description: 数据库的插入的操作 * @param @param tableName * @param @param tableHeadJ 参数说明 * @return void 返回类型 * @throws */ public void insertTable(String tableName, Vector<String> tableData) { if(JavaDataBaseUtil.isTable(tableName)){ List<String> list = new ArrayList<String>(); String tablePath = JdbcDataUtil.dataPathCVS + tableName+".csv"; String identityKeyPath = JdbcDataUtil.identityPath; //读取书库中的数据 Vector<String> vecTemp = JavaDataBaseUtil.getDataRead(tablePath); Vector<String> identity = JavaDataBaseUtil.getDataRead(identityKeyPath); if(vecTemp.size() == 0){ System.out.println("error : 插入的数据无表头：JdbcBasicImpl.insertTable(String tableName, Vector<String> tableContent)"); return; }else { boolean flag = false; String strTemp = ""; int index = tableData.size(); int headLength = vecTemp.get(0).split(",").length; for(String iden : identity){ String[] str = iden.split(","); if(tableName.equals(str[0])){ index = tableData.size()+1; flag = true; } } if (headLength != index) { System.out.println("error : 插入数据与表头不符：JdbcBasicImpl.insertTable(String tableName, Vector<String> tableContent)"); return; }else { //存在自增 if(flag){ int conter = vecTemp.size(); String num = "0"; if(conter > 1){ num = vecTemp.get(conter-1).split(",")[0]; } strTemp = ""+(Integer.parseInt(num)+1)+""; for (int i = 0; i < tableData.size(); i++) { strTemp += (","+tableData.elementAt(i)); } }else{ for (int i = 0; i < headLength; i++) { if (i==0) { strTemp = tableData.elementAt(0); }else { strTemp += (","+tableData.elementAt(i)); } } } list.add(strTemp); JavaDataBaseUtil.getDataWrite(tablePath, list); } } }else{ System.out.println("error : 插入出错，不存在此表：【JdbcBasicImpl.insertTable(String tableName, Vector<String> tableData)】"); return; } } /** * @Title: selectAllTable * @Description: 查询所有的数据 * @param @param tableName 参数说明 * @return void 返回类型 * @throws */ public List<Object[]> selectAllTable(String tableName,String filed){ if(JavaDataBaseUtil.isTable(tableName)){ List<Object[]> list = new ArrayList<Object[]>(); Vector<String> result = selectAllResult(tableName); if(filed != null){ selectFiledTable(list, result,filed); return list; } for(int i=1;i<result.size();i++){ String data = result.get(i); String[] query = data.split(","); Object[] obj = new Object[query.length]; for(int j=0;j<query.length;j++){ obj[j] = query[j]; } list.add(obj); } return list; }else{ System.out.println("error : 查询出错，不存在此表：【JdbcBasicImpl.selectAllTable(String tableName,String filed)】"); return null; } } /** * @Title: selectFiledTable * @Description: 查询所有，并指定返回的字段数据 * @param @param list * @param @param result * @param @param filed * @param @return 参数说明 * @return List<Object[]> 返回类型 * @throws */ public static List<Object[]> selectFiledTable(List<Object[]> list,Vector<String> result,String filed){ String[] str = filed.split(","); String[] res = result.get(0).split(","); List<Integer> index = new ArrayList<Integer>(); //字段匹配,不区分大小写 for(int i = 0; i<str.length; i++){ for(int j = 0 ;j < res.length; j++){ if(str[i].toLowerCase().equals(res[j].toLowerCase())){ index.add(j); } } } //根据下标获取数据 for(int i=1 ; i<result.size() ; i++){ int conter = 0; String data = result.get(i); String[] query = data.split(","); Object[] obj = new Object[str.length]; for(int j=0;j<query.length;j++){ if(index.contains(j)){ obj[conter] = query[j]; conter++; } } list.add(obj); } return list; } /** * @Title: selectOneOpreTable * @Description: where的条件查询，根据运算符判断，得到数据 * @param @param tableName * @param @param dataList * @param @param oper * @param @return 参数说明 * @return List<Object[]> 返回类型 * @throws */ public List<Object[]> selectOneOpreTable(String tableName,List<String> dataList,List<String> oper,List<String> listAll){ if(JavaDataBaseUtil.isTable(tableName)){ List<Object[]> list = new ArrayList<Object[]>(); Map<String, Object[]> map = new HashMap<String,Object[]>(); List<Object[]> list1 = new ArrayList<Object[]>(); List<Object[]> list2 = new ArrayList<Object[]>(); Vector<String> result = selectAllResult(tableName); String fileds = result.get(0); if(oper != null){ String operator = getOper(result, dataList.get(0)); String operator1 = getOper(result, dataList.get(1)); if(operator != null && operator1 != null){ if(JdbcBasicPro.getOperator().contains(operator) && JdbcBasicPro.getOperator().contains(operator1)){ Map<String, Object[]> mapValue1 = null; Map<String, Object[]> mapValue2 = null; if(listAll.size() != 0){ mapValue1 = JdbcBasicPro.getDataOperator(operator, result , dataList.get(0)); mapValue2 = JdbcBasicPro.getDataOperator(operator1, result , dataList.get(1)); sepDataSelectTable(list1, mapValue1, listAll.get(0), fileds); sepDataSelectTable(list2, mapValue2, listAll.get(0), fileds); }else{ mapValue1 = JdbcBasicPro.getDataOperator(operator, result , dataList.get(0)); mapValue2 = JdbcBasicPro.getDataOperator(operator1, result , dataList.get(1)); } if(oper.contains(JdbcBasicPro.and.toString())){ for(Map.Entry<String, Object[]> entry : mapValue1.entrySet()){ if(mapValue2.containsKey(entry.getKey())){ //判断value的值是否相同 Object[] isObj = entry.getValue(); Object[] obj = mapValue2.get(entry.getKey()); boolean flag = true; for(int i=0;i<obj.length;i++){ if(!isObj[i].equals(obj[i])){ flag =false; } } if(flag){ list.add(entry.getValue()); } } } }else{ map.putAll(mapValue1); map.putAll(mapValue2); for(Map.Entry<String, Object[]> entry : map.entrySet()){ list