Hibernate JPA Specification重写toPredicate多条件查询

深碍√TFBOYSˉ_ 2022-06-17 13:50 230阅读 0赞

使用手册实体类,省略了getter/setter

@Entity
    @Table(name="manual")
    public class Manual {
    	
    	@Id
    	@GeneratedValue
    	private Long id;
    	/**
    	 * 文件名称
    	 */
    	@Column(name="filename")
    	private String fileName;
    
    	/**
    	 * 应用类型
    	 */
    	@JsonIgnore
    	@ManyToOne(fetch=FetchType.LAZY)
    	@JoinColumn(name="applicationid")
    	private Application application;

使用手册实体Bean

public class ManualListBean {
    
    	private final Manual manual;
    	
    	public ManualListBean(Manual manual){
    		this.manual = manual;
    	}
    	@JsonView(DataTablesOutput.View.class)
    	public Long getId(){
    		return manual.getId();
    	}
    	@JsonView(DataTablesOutput.View.class)
    	public String getFileName(){
    		return manual.getFileName();
    	}
    	
    	@JsonView(DataTablesOutput.View.class) public String getApplicationName(){ Application application = manual.getApplication(); if(application != null){ return application.getName(); } return ""; }
    }

应用类型实体类,省略了getter/setter

@Entity
    @Table(name = "applicationtype")
    public class ApplicationType implements java.io.Serializable{
    
    	private static final long serialVersionUID = 899339761892494451L;
    
    	@Id
        @GeneratedValue(strategy = GenerationType.IDENTITY)
    	private Long id;
    	
    	@Column(name = "name")
    	private String name;//应用名称
    
    	@JsonIgnore
    	@OneToMany(fetch=FetchType.LAZY, mappedBy="applicationType",cascade=CascadeType.ALL)
    	private Set<InstructionManual> instructionManualSet = new HashSet<>();

Bean

public class ApplicationListBean extends DataTableBean<Application>{
    	@JsonView(DataTablesOutput.View.class)
    	public Long getId() {
    		return target.getId();
    	}
    	
    	@JsonView(DataTablesOutput.View.class)
    	public String getName() {
    		return target.getName();
    	}
    
    }

ManualController

@JsonView(DataTablesOutput.View.class)
    	@RequestMapping(value="/manualList.json",method=RequestMethod.POST)
    	@ResponseBody
    	public DataTablesOutput<ManualListBean> manualList(@Valid DataTablesInput input, HttpServletRequest request){
    		Test test = (Test) request.getSession().getAttribute("test");
    		List<Application> applications = applicationService.findByApplication(test);
    		final Set<Application> applicationSet = new HashSet<>(applications);
    		final String name = ".xxx";
    		Specification<Manual> additionalSpecification = new Specification<Manual>() {
    			@Override
    			public Predicate toPredicate(Root<Manual> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
    				if(applicationSet.size()>0){
    					List<Predicate> predicateList = new ArrayList<>();
    					Iterator<Application> iterator = applicationSet.iterator();
    					while(iterator.hasNext()){ 
    						Application application = iterator.next();
    						Predicate p1 = cb.equal(root.<Application>get("application"), application);
    						predicateList.add(p1);	
    					}
    					Predicate[] pre = new Predicate[predicateList.size()];
    					query.where(predicateList.toArray(pre));
    				}else{
    					Predicate p1 = cb.equal(root.<String>get("filename"), name);
    					query.where(p1);
    				}
    				return query.getRestriction(); 
    			}
    		};
    		DataTablesOutput<Manual> manualOutput = this.manualService.findAll(input, additionalSpecification);
    		DataTablesOutput<ManualListBean> output = new DataTablesOutput<>();
    		output.setDraw(manualOutput.getDraw());
    		output.setError(manualOutput.getError());
    		output.setRecordsFiltered(manualOutput.getRecordsFiltered());
    		output.setRecordsTotal(manualOutput.getRecordsTotal());
    		List<ManualListBean> listData = new ArrayList<>();
    		for (Manual manual : manualOutput.getData()) {
    			ManualListBean manualListBean = new ManualListBean(manual);
    			listData.add(manualListBean);
    		}
    		output.setData(listData);
    		return output;
    	}

前端

$(function() {
    	$('#form').DataTable({
    		serverSide : true,
    		destroy : true,
    		ajax : {
    			url : ctx + '/manual/manualList.json',
    			type : "post"
    		},
    		columns : [
    		           {"data" : "id"},
    		           {"data" : "fileName"},
    		           {"data" : "application.name"},
    		           {"data" : "id"}
    		],
    		columnDefs : [{
    		            	    width : '11%',
    			       			render : function(data, type, row) {
    			       				return data;
    			       			},
    			       			targets: [0,1]
    		               },
    		               {
    			                width: '20%',
    			                render: function (data, type, row) {
    			                    return row.applicationName;
    			                },
    			                targets: [2]
    			           },
    		               {
    			width : '20%',
    			render : function(data, type, row) {
    			if (data) {var html = '<ul class="icons-list"><li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown">'
    			+ '<i class="icon-menu9"></i></a>'
    			+ '<ul class="dropdown-menu dropdown-menu-right">'
    											
    			+ '<li><a href="'+ ctx + '/manual/update/'+ data+ '"><i class="icon-diff-modified"></i>操作</a></li>'
    											
    			+ '</ul></li></ul>';
    									return html;
    								} else {
    									return '';
    								};
    							},
    							targets : 3,
    						}]
    
    	});
    });

参考:http://www.knowsky.com/988841.html