使用QueryRunner 结合c3p0进行数据库操作时候，
需求：list<bean>进行插入数据库中，但是QueryRunner 仅仅支持batch()：批处理；
Object[][] params = null;qr.batch("insert into MyTable (param1,param2,param3) values (?,?,?)", params);
需要把后面的参数设置成二维数组，但是如何设置成这种二维数组呢，下面提供类ModelToSqlConverter.javapackage com.htzq.dbutil;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;
public class ModelToSqlConverter {
private Object model;
private List<Object> params, keyParams, modelList;
private String fieldNameString, questionMarkString, sqlString, conditionString, updateString;
private boolean update;
private String[] keys;
private Object[][] multiParams;
/**
* Initializes a newly created <code>ModelToSqlConverter</code>
*
* @param model The model representing the ASW file.
* @param keys The keys for locating the right row in ASW file.
*/
@SuppressWarnings("unchecked")
public ModelToSqlConverter(Object model, String... keys){
this.model = model;
this.keys = keys;
params = new ArrayList<Object>();
keyParams = new ArrayList<Object>();
questionMarkString = "VALUES (";
fieldNameString = "(";
updateString = "";
conditionString = "WHERE ";
update = keys != null && keys.length > 0;
if(model instanceof List<?>){
modelList = (List<Object>) model;
convertModelListToSqlAndParams();
}else{
convertModelToSqlAndParams();
}
}
/**
* Main method for Converting Model into SQL String and to value parameters.
*/
private void convertModelToSqlAndParams(){
for(Field field : model.getClass().getDeclaredFields()){
try{
field.setAccessible(true);
Object value = field.get(model);
String fieldName = field.getName();
if(value != null && !fieldName.equalsIgnoreCase("serialVersionUID")){
if(!update){
addQuestionMark();
addNameToSql(fieldName);
addValueToObjectArray(value);
}else{
if(isKey(fieldName)){
conditionString += fieldName + " = ?,";
keyParams.add(value);
}else{
addParamAndNameToSql(fieldName);
addValueToObjectArray(value);
}
}
}
}catch(IllegalArgumentException e){
// TODO Auto-generated catch block
e.printStackTrace();
}catch(IllegalAccessException e){
// TODO Auto-generated catch block
e.printStackTrace();
}
}
sqlString = update ? getUpdateSql() : getInsertSql();
for(Object key : keyParams){
addValueToObjectArray(key);
}
}
/**
* Main method for Converting Model into SQL String and to value parameters.
*/
private void convertModelListToSqlAndParams(){
int row = 0;
boolean isKey = false;
boolean firstModel = true;
Field[] fields = modelList.get(0).getClass().getDeclaredFields();
multiParams = new Object[modelList.size()][fields.length];
for(Object model : modelList){
int col = 0;
keyParams = new ArrayList<Object>();
for(Field field : fields){
try{
field.setAccessible(true);
Object value = field.get(model);
String fieldName = field.getName();
if(value != null && !fieldName.equalsIgnoreCase("serialVersionUID")){
if(!update){
if(firstModel){
addQuestionMark();
addNameToSql(fieldName);
}
addValueToMultiParams(value, row, col);
}else{
isKey = isKey(fieldName);
if(isKey){
if(firstModel){
conditionString += fieldName + " = ?,";
}
keyParams.add(value);
}else{
if(firstModel)
addParamAndNameToSql(fieldName);
addValueToMultiParams(value, row, col);
}
}
}
}catch(IllegalArgumentException e){
// TODO Auto-generated catch block
e.printStackTrace();
}catch(IllegalAccessException e){
// TODO Auto-generated catch block
e.printStackTrace();
}
if(!isKey)
col++;
}
firstModel = false;
for(Object key : keyParams){
addValueToMultiParams(key, row, col);
col++;
}
row++;
}
sqlString = update ? getUpdateSql() : getInsertSql();
}
/**
* @param columnName
*/
private void addNameToSql(String columnName){
fieldNameString += columnName + ",";
}
/**
* @param value
*/
private void addValueToObjectArray(Object value){
params.add(value);
}
/**
* @param value
* @param row
* @param col
*/
private void addValueToMultiParams(Object value, int row, int col){
multiParams[row][col] = value;
}
public Object[][] getMultiValueParams(){
return removeNullsFromMultiArray(multiParams);
}
/**
* Adds question mark to string
*/
private void addQuestionMark(){
questionMarkString += "?,";
}
/**
* @param columnName
*/
private void addParamAndNameToSql(String columnName){
updateString += columnName + "= ?,";
}
/**
* @return the update SQL string.
*/
private String getUpdateSql(){
return updateString.substring(0, updateString.lastIndexOf(",")) + " " + conditionString.substring(0, conditionString.lastIndexOf(","));
}
/**
* @return the insert SQL string.
*/
private String getInsertSql(){
return fieldNameString.substring(0, fieldNameString.lastIndexOf(",")) + ") " + questionMarkString.substring(0, questionMarkString.lastIndexOf(","))
+ ")";
}
private Object[][] removeNullsFromMultiArray(Object[][] multiValuedArray){
for(int i = 0; i < multiValuedArray.length; i++){
ArrayList<Object> list = new ArrayList<Object>(); // creates a list to store the elements !=
// null
for(int j = 0; j < multiValuedArray[i].length; j++){
if(multiValuedArray[i][j] != null){
list.add(multiValuedArray[i][j]); // elements != null will be added to the list.
}
}
multiValuedArray[i] = list.toArray(new Object[list.size()]); // all elements from list to an
// array.
}
return multiValuedArray;
}
/**
* Checks if the field name is a key.
*
* @param fieldName
* @return true if the field is a key.
*/
private boolean isKey(String fieldName){
boolean isKey = false;
for(String key : keys){
if(fieldName.equalsIgnoreCase(key)){
isKey = true;
}
}
return isKey;
}
/**
* @return the params
*/
public Object[] getParams(){
return params.toArray();
}
/**
* @return the sqlString
*/
public String getSqlString(){
return sqlString;
}
/**
* @param params the params to set
*/
public void setParams(List<Object> params){
this.params = params;
}
/**
* @param sqlString the sqlString to set
*/
public void setSqlString(String sqlString){
this.sqlString = sqlString;
}
}
C3P0MySqlConnection.java
1 package com.htzq.dbutil;
2
3 import java.beans.PropertyVetoException;
4 import java.sql.SQLException;
5
6 import com.mchange.v2.c3p0.ComboPooledDataSource;
7
8 public class C3P0MySqlConnection {
9
10 public ComboPooledDataSource C3P0SqlServerConnection(String []a) throws SQLException {
11 ComboPooledDataSource ds = new ComboPooledDataSource() ;
12 try {
13 ds = new ComboPooledDataSource();//创建连接池实例
14 ds.setDriverClass("com.mysql.jdbc.Driver");//设置连接池连接数据库所需的驱动
15 ds.setJdbcUrl(a[0]);//设置连接数据库的URL
16 ds.setUser(a[1]);//设置连接数据库的用户名
17 ds.setPassword(a[2]);//设置连接数据库的密码
18 ds.setMaxPoolSize(40);//设置连接池的最大连接数
19 ds.setMinPoolSize(2);//设置连接池的最小连接数
20 ds.setInitialPoolSize(5);//设置连接池的初始连接数
21 ds.setMaxStatements(100);//设置连接池的缓存Statement的最大数
22 } catch (PropertyVetoException e) {
23 // TODO Auto-generated catch block
24 e.printStackTrace();
25 }
26 return ds;
27
28 }
29 }
逻辑处理
1 String sql = sqlBuf.substring(0, sqlBuf.length()-10); 2 List<ShWtqr> list = iSysConfigDao.selectSysCollect(a ,sql); 3 4 a = readPropertiesUtil.readMySqlPro(); 5 ModelToSqlConverter modelToSqlConverter = new ModelToSqlConverter(list); 6 String mysql = "INSERT INTO " + list.get(0).getClass().getSimpleName().toUpperCase() + " " + modelToSqlConverter.getSqlString(); 7 8 int v = iSysConfigDao.insertSysCollect(a ,mysql,modelToSqlConverter.getMultiValueParams());
insertSysCollect函数如下
1 @Override
2 public int insertSysCollect(String[] a,String sql, Object[][] c) {
3 List<ShWtqr> list = null;
4 try {
5 C3P0MySqlConnection c3p0MySqlConnection = new C3P0MySqlConnection();
6 ComboPooledDataSource ds = c3p0MySqlConnection.C3P0SqlServerConnection(a);
7
8 QueryRunner queryRunner = new QueryRunner(ds);
9 int []b = queryRunner.batch(sql, c);
10 } catch (SQLException e) {
11 // TODO Auto-generated catch block
12 e.printStackTrace();
13 }
14 return 0;
15 }
时间： 2024-07-28 17:28:12