Ofiz一些查询示例

[size=x-large][color=red]Ofbiz架构讲解与讨论[/color][/size][url]http://wenku.baidu.com/view/b631f311f18583d049645903[/url]
[b] 1. 创建记录 [/b] 

Map planetValues = UtilMisc.toMap("planetId", "JUPITER", " planetName", "Jupiter"); 
GenericValue planetGV = delegator.makeValue("Planet", planetValues); planetGV.create();

UtilMisc是集合类操作的工具类，ofbiz优化了map，list，set。 GenericValue 对象是对应数据库中一条记录。  

以上代码等价于 

INSERT INTO Planet (planetId, planetName)  VALUES ("JUPITER", "Jupiter"). 

[b]2. 更新记录 [/b] 

Map planetValues = UtilMisc.toMap("planetId", "JUPITER"); 
GenericValue planetGV = delegator.findByPrimaryKey("Planet",planetValues); planetGV.put("planetName", "Joopiter"); planetGV.store();

 以上代码等价于 

UPDATE Planet  SET planetName = "Joopiter"  WHERE planetId = "JUPITER" 

[b]3. 删除记录  [/b]

Map planetValues = UtilMisc.toMap("planetId", "JUPITER"); 
GenericValue planetGV = delegator.findByPrimaryKey("Planet",  planetValues); planetGV.remove();

以上代码等价于 

DELETE FROM Planet WHERE planetId = "JUPITER"  

[b]4. 查询记录  [/b]

condition = new EntityExpr("planetId", EntityOperator.EQUALS, "EARTH"); data = delegator.findByCondition("Planet", condition, null, null);

 以上代码等价于 

SELECT * FROM Planet WHERE planetId = "EARTH" 其中 

EntityOperator 为ofbiz逻辑操作符号类。 

EQUALS NOT_EQUAL LESS_THAN GREATER_THAN 

LESS_THAN_EQUAL_TO (less than or equal to) GREATER_THAN_EQUAL_TO IN NOT_IN BETWEEN LIKE NOT_LIKE NOT  

[b]findByCondition(entityName,condition,filedList,orderList)[/b]方法的四个参数。 

entityName：查询的实体名 

condition ：查询条件 

filedList ：实体属性列表 

orderList ： 属性排序列表  

fields = UtilMisc.toList("planetId", "planetName"); 
data = delegator.findByCondition("Planet", condition, fields, null);

 以上代码等价于 

SELECT  plantetId,name  FROM  Planet  

fields = UtilMisc.toList("planetId DESC"); //fields = UtilMisc.toList("-planetId ");

以上代码等价于 

SELECT * FROM Planet ORDER BY planetId DESC  

[b]模糊查询 [/b]

condition = new EntityExpr("planetName", EntityOperator.LIKE,  "%AR%"); data = delegator.findByCondition("Planet", condition, null, null);

以上代码等价于 

SELECT * FROM Planet WHERE planetName LIKE "%ar%"  

[b]复合条件查询 [/b]

conditionList = UtilMisc.toList  
  (new EntityExpr("planetName", EntityOperator.LIKE, "%ar%"),     new EntityExpr("planetName", EntityOperator.LIKE, "%m%")); condition1 = new EntityConditionList(conditionList,   
                                     EntityOperator.OR); condition2 = new EntityConditionList  
  (UtilMisc.toList(new EntityExpr("planetName", EntityOperator.LIKE, "%s%"),      new EntityExpr("planetName", EntityOperator.LIKE, "%P%")),     EntityOperator.OR); 
combined = new EntityConditionList(UtilMisc.toList(condition1, condition2), EntityOperator.AND); data = delegator.findByCondition("Planet", combined, null, null);

以上代码等价于 SELECT  * FROM  

Planet 

WHERE  

(planetName LIKE "%ar%" OR planetName LIKE "%t%") AND  

(planetName LIKE "%s%" OR planetName LIKE "%P%") 

[size=x-large][color=red]Accessing the Entities and View Entities[/color][/size][url]

[b]无条件遍历[/b]

使用如下代码即可：

findList(EntityName, null, null, null, null,false);

[b][color=red]条件遍历[/color][/b]

需要先了解如下概念：

条件的表达

EntityWhereString - SQL语句描述，OFBiz的开发者强烈不建议使用这个，因为破坏了OFBiz的封装性

EntityExpr - 使用OFBiz封装好的操作符来描述一个条件，推荐使用，简单易懂。EntityExpr = 左值 + operator + 右值。我们使用EntityCondition.makeCondition()来生成EntityExpr

EntityOperator - 定义了条件中的操作符

EQUALS，NOT_EQUAL，LESS_THAN，GREATER_THAN，LESS_THAN_EQUAL_TO (less than or equal to)，GREATER_THAN_EQUAL_TO - 用于数值的比较

condition = EntityCondition.makeCondition("planetId", EntityOperator.NOT_EQUAL,"EARTH");

IN，NOT_IN - 规定遍历的结果的某个属性值需要在/不在某个集合中

condition = EntityCondition.makeCondition("planetId", EntityOperator.IN, UtilMisc.toList("EARTH", "PLUTO"))；

LIKE，NOT_LIKE - 用于字符串匹配

condition = new EntityExpr("planetName", EntityOperator.LIKE, "%AR%");

这里的意思是找出名字里面还有AR的所有planet

% - any number of characters

_ - any one character

EntityConditionList - 由多个EntityExpr连接来。 EntityConditionList = list_of(condition1，condition2，...) + EntityJoinOperator

conditionList = UtilMisc.toList(EntityCondition.makeCondition("planetName", EntityOperator.LIKE, "%ar%"),   
                    EntityCondition.makeCondition("planetName", EntityOperator.LIKE, "%t%"));  
conditions = EntityCondition.makeCondition(conditionList, EntityOperator.AND);

EntityJoinOperator - 两个值AND和OR。其实它是继承EntityOperator得来的，所以使用EntityOperator.AND和EntityOperator.OR也行

public List<GenericValue> findList(String entityName, EntityCondition entityCondition, Set<String> fieldsToSelect, List<String> orderBy, EntityFindOptions findOptions, boolean useCache) - 返回查找的列表

entityName

entityCondition - 查找的条件，可以为EntityExpr，也可以为EntityConditionList，因为他们都是继承于EntityCondition的

fieldsToSelect - 结果中需要显示field，即选择要显示的列

orderBy - 结果的排序，排序的规则是：orders the retrieved records by those fields. If there is more than one field in the list, ordering is performed by the first field, then the second, and so on。默认是升序排列。如果要降序排列，可以这样：

order = UtilMisc.toList("planetId DESC");

注意：此处planetId和DESC之间的空格有且只能有一个，多了少了都会出错，其他地方有多少个空格都无所谓

或者

order = UtilMisc.toList("-planetId");

注意：-和planetId之间不能有空格，否则出错，其他地方空格随意

findOptions - 不常用，设为null

useCache - 不常用，设为false

[b]单一条件查找[/b]

import org.ofbiz.base.util.*;  
import org.ofbiz.entity.*;  
import org.ofbiz.entity.condition.*;  

condition = EntityCondition.makeCondition("planetId", EntityOperator.IN,UtilMisc.toList("EARTH", "PLUTO"));  
data = delegator.findList("Planet", condition, null, null, null,false);

[b]多条件查找[/b]

[b]import org.ofbiz.base.util.*;

import org.ofbiz.entity.*;

import org.ofbiz.entity.condition.*;

conditionList = UtilMisc.toList(EntityCondition.makeCondition("planetName", EntityOperator.LIKE, "%ar%"),

EntityCondition.makeCondition("planetName", EntityOperator.LIKE, "%t%"));

conditions = EntityCondition.makeCondition(conditionList, EntityOperator.AND);

data = delegator.findList("Planet", conditions, null, null, null,false); [/b]

[b]查找结果排序[/b]

import org.ofbiz.base.util.*;  
order = UtilMisc.toList("planetId DESC");  
data = delegator.findList("Planet", null, null, order, null, false);

[b]选择要结果中Field[/b]

import org.ofbiz.base.util.*;  
fields = UtilMisc.toSet("planetId", "planetName");  
data = delegator.findList("Planet", null, fields, null, null, false);

[color=red][b]分页[/b][/color]

int listSize = 0;
				int lowIndex = 0;
				int highIndex = 0;
				int viewSize = 10;

				lowIndex = (Integer.parseInt(pagenumber) - 1) * viewSize + 1;
				highIndex = Integer.parseInt(pagenumber) * viewSize;

				List<GenericValue> list = null;
				String entityName = "SandbagUserTotalScoreProgramView";
				TransactionUtil.begin();
				EntityListIterator pli = null;
				Set<String> fieldToSet = FastSet.newInstance();
				List<String> orderBy = FastList.newInstance();
				orderBy.add("-score");

				EntityFindOptions findOpts = new EntityFindOptions();
				findOpts.setResultSetType(EntityFindOptions.TYPE_SCROLL_INSENSITIVE);
				findOpts.setMaxRows(15);
				List<EntityCondition> mainCondList = FastList.newInstance();
				if (UtilValidate.isNotEmpty(traineeId)) {
					mainCondList.add(EntityCondition.makeCondition("traineeId", EntityOperator.EQUALS, traineeId));
				}
				mainCondList.add(EntityCondition.makeCondition("fromType", EntityOperator.EQUALS, "program"));

				EntityCondition mainCond = EntityCondition.makeCondition(mainCondList, EntityOperator.AND);

				pli = delegator.find(entityName, mainCond, null, fieldToSet, orderBy, findOpts);
				if (lowIndex > 0 && viewSize > 0) {
					list = pli.getPartialList(lowIndex, viewSize);
				} else {
					list = pli.getCompleteList();
				}

				listSize = pli.getResultsSizeAfterPartialList();
				if (highIndex > listSize) {
					highIndex = listSize;
				}
				TransactionUtil.commit();

				success = "1";
				resultObj.put("rows", viewSize);
				resultObj.put("total", listSize);
				resultObj.put("pagecount", listSize % viewSize > 0 ? listSize / viewSize + 1 : listSize / viewSize);
				resultObj.put("data", parseViewDatList(list));
				resultObj.put("success", success);