使用Gradle: com.google.guava:guava:16.0.1 jar文件
通过com.google.common.collect.Iterables和com.google.common.base.Predicate功能实现简单条件查询过滤
完整代码：
/**
* query monitor zknodes list
* @param currentPageNum
* @param pageSize
* @param nodeName
* @return
*/
@RequestMapping(value = "/list", method = RequestMethod.GET)
public ResponseEntity<PageableRetVO<List<MonitorNodesParam>>> getMonitorZnodeList(
@RequestParam(value = "currentPageNum", required = false) Integer currentPageNum,
@RequestParam(value = "pageSize", required = false) Integer pageSize,
@RequestParam(value = "nodeName", required = false) String nodeName){
final String nodeNameQry = nodeName;
PageableRetVO<List<MonitorNodesParam>> pageableRetVO = new PageableRetVO<>();
try {
createConnectZk();
List<MonitorNodesParam> znodes = zkFacade.readConfigFromZk();
// 1.filter
List<MonitorNodesParam> filteredList = Lists.newArrayList();
if(StringUtils.isNotEmpty(nodeNameQry)){
Iterable<MonitorNodesParam> filteredIter = Iterables.filter(znodes, new Predicate<MonitorNodesParam>() {
@Override
public boolean apply(MonitorNodesParam input) {
if (StringUtils.isNotEmpty(nodeNameQry) && input.getNodeName().contains(nodeNameQry)) {
return true;
} else {
return false;
}
}
});
for(MonitorNodesParam filtered:filteredIter){
filteredList.add(filtered);
}
}else{
filteredList = znodes;
}
// 2.page
int totalCount = filteredList.size();
pageableRetVO.setTotalCount(totalCount);
pageableRetVO.setPageNum((currentPageNum==null?0:currentPageNum) > 0 ? currentPageNum : 1);
pageableRetVO.setPageSize((pageSize == null ? 0 : pageSize) <= 0 ? 20 : pageSize);
int totalPagesNum = BaseUtils.getPagesNum(filteredList.size(), pageableRetVO.getPageSize());
if(pageableRetVO.getPageNum()<=totalPagesNum){
filteredList = filteredList.subList((pageableRetVO.getPageNum()-1) * pageableRetVO.getPageSize(), Math.min(filteredList.size(),(pageableRetVO.getPageNum())*pageableRetVO.getPageSize()));
pageableRetVO.setList(filteredList);
}else{
pageableRetVO.setList(new ArrayList<MonitorNodesParam>());
}
pageableRetVO.setRetCode(0);
} catch (Exception e) {
logger.error(e.getMessage());
pageableRetVO.setRetCode(-1);
pageableRetVO.setErrorMsg(e.getMessage());
}
return new ResponseEntity<>(pageableRetVO, HttpStatus.OK);
}