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java 中mongodb的各种操作查询的实例详解
一. 常用查询:
1. 查询一条数据:(多用于保存时判断db中是否已有当前数据,这里 is 精确匹配,模糊匹配 使用regex...)
public PageUrl getByUrl(String url) {
return findOne(new Query(Criteria.where("url").is(url)),PageUrl.class);
}2. 查询多条数据:linkUrl.id 属于分级查询
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public List<PageUrl> getPageUrlsByUrl(int begin, int end,String linkUrlid) {
Query query = new Query();
query.addCriteria(Criteria.where("linkUrl.id").is(linkUrlid));
return find(query.limit(end - begin).skip(begin), PageUrl.class);
}3.模糊查询:-----关键字---regex
public long getProcessLandLogsCount(List<Condition> conditions)
{
Query query = new Query();
if (conditions != null && conditions.size() > 0) {
for (Condition condition : conditions) {
query.addCriteria(Criteria.where(condition.getKey()).regex(".*?\" +condition.getValue().toString()+ ".*"));
}
}
return count(query, ProcessLandLog.class);
}最下面，我在代码亲自实践过的模糊查询，只支持字段属性是字符串的查询，你要是查字段属性是int的模糊查询，还真没辙。
4.gte: 大于等于,lte小于等于...注意查询的时候各个字段的类型要和mongodb中数据类型一致
public List<ProcessLandLog> getProcessLandLogs(int begin,int end,List<Condition> conditions,String orderField,Direction direction)
{
Query query = new Query();
if (conditions != null && conditions.size() > 0) {
for (Condition condition : conditions) {
if(condition.getKey().equals("time")){
query.addCriteria(Criteria.where("time").gte(condition.getValue())); //gte: 大于等于
}else if(condition.getKey().equals("insertTime")){
query.addCriteria(Criteria.where("insertTime").gte(condition.getValue()));
}else{
query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue()));
}
}
}
return find(query.limit(end - begin).skip(begin).with(new Sort(new Sort.Order(direction, orderField))), ProcessLandLog.class);
}
public List<DpsLand> getDpsLandsByTime(int begin, int end, Date beginDate,Date endDate) {
return find(new Query(Criteria.where("updateTime").gte(beginDate).lte(endDate)).limit(end - begin).skip(begin),
DpsLand.class);
}查询字段不存在的数据 -----关键字---not
public List<GoodsDetail> getGoodsDetails2(int begin, int end) {
Query query = new Query();
query.addCriteria(Criteria.where("goodsSummary").not());
return find(query.limit(end - begin).skip(begin),GoodsDetail.class);
}查询字段不为空的数据 -----关键字---ne
Criteria.where("key1").ne("").ne(null)查询或语句：a || b ----- 关键字---orOperator
Criteria criteria = new Criteria();
criteria.orOperator(Criteria.where("key1").is("0"),Criteria.where("key1").is(null));查询且语句：a && b ----- 关键字---and
Criteria criteria = new Criteria();
criteria.and("key1").is(false);
criteria.and("key2").is(type);
Query query = new Query(criteria);
long totalCount = this.mongoTemplate.count(query, Xxx.class);查询一个属性的子属性，例如：查下面数据的key2.keyA的语句
var s = {
key1: value1,
key2: {
keyA: valueA,
keyB: valueB
}
};
@Query("{'key2.keyA':?0}")
List<Asset> findAllBykeyA(String keyA);5. 查询数量:----- 关键字---count
public long getPageInfosCount(List<Condition> conditions) {
Query query = new Query();
if (conditions != null && conditions.size() > 0) {
for (Condition condition : conditions) {
query.addCriteria(Criteria.where(condition.getKey()).is(condition.getValue()));
}
}
return count(query, PageInfo.class);
}查找包含在某个集合范围：----- 关键字---in
Criteria criteria = new Criteria();
Object [] o = new Object[]{0, 1, 2}; //包含所有
criteria.and("type").in(o);
Query query = new Query(criteria);
query.with(new Sort(new Sort.Order(Direction.ASC, "type"))).with(new Sort(new Sort.Order(Direction.ASC, "title")));
List<WidgetMonitor> list = this.mongoTemplate.find(query, WidgetMonitor.class);6. 更新一条数据的一个字段:
public WriteResult updateTime(PageUrl pageUrl) {
String id = pageUrl.getId();
return updateFirst(new Query(Criteria.where("id").is(id)),Update.update("updateTime", pageUrl.getUpdateTime()), PageUrl.class);
}7. 更新一条数据的多个字段:
//调用更新
private void updateProcessLandLog(ProcessLandLog processLandLog,
int crawlResult) {
List<String> fields = new ArrayList<String>();
List<Object> values = new ArrayList<Object>();
fields.add("state");
fields.add("result");
fields.add("time");
values.add("1");
values.add(crawlResult);
values.add(Calendar.getInstance().getTime());
processLandLogReposity.updateProcessLandLog(processLandLog, fields,
values);
}
//更新
public void updateProcessLandLog(ProcessLandLog land, List<String> fields,List<Object> values) {
Update update = new Update();
int size = fields.size();
for(int i = 0 ; i < size; i++){
String field = fields.get(i);
Object value = values.get(i);
update.set(field, value);
}
updateFirst(new Query(Criteria.where("id").is(land.getId())), update,ProcessLandLog.class);
}8. 删除数据:
public void deleteObject(Class<T> clazz,String id) {
remove(new Query(Criteria.where("id").is(id)),clazz);
}9.保存数据:
//插入一条数据
public void saveObject(Object obj) {
insert(obj);
}
//插入多条数据
public void saveObjects(List<T> objects) {
for(T t:objects){
insert(t);
}
}我自己使用的例子：
下面例子涉及到：
精确查询：is；
模糊查询：regex；
分页查询，每页多少：skip，limit
按某个字段排序(或升或降)：new Sort(new Sort.Order(Sort.Direction.ASC, "port"))
查询数量：count
public Map<String, Object> getAppPortDetailByPage(int pageNo, int pageSize, String order, String sortBy, String appPortType, String appPortSeacherName) {
Criteria criteria = new Criteria();
if (!appPortType.equals("")) {
if (!appPortType.equals("all")) {
//DB表里的字段----appmanageType
//下同 port protocol 也是DB表的字段
criteria.and("appmanageType").is(appPortType);
}
}
if (!appPortSeacherName.equals("")) {
try {
criteria.orOperator(Criteria.where("port").is(Integer.parseInt(appPortSeacherName)),
Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*"));
}catch (Exception e){
criteria.orOperator(Criteria.where("protocol").regex(".*?" + appPortSeacherName + ".*"));
}
}
Map<String, Object> result = Maps.newHashMap();
Query query = new Query(criteria);
query.skip((pageNo - 1) * pageSize);
query.limit(pageSize);
if(order != null && sortBy != null){
query.with(new Sort(new Sort.Order(order.equals("asc") ? Sort.Direction.ASC : Sort.Direction.DESC, sortBy)));
}else {
query.with(new Sort(new Sort.Order(Sort.Direction.ASC, "port")));
}
List<Appportmanage> list = this.mongoTemplate.find(query, Appportmanage.class);
long count = this.mongoTemplate.count(query, Appportmanage.class);
result.put("datas", list);
result.put("size", count);
return result;
} 
