二十八、SpringBoot中使用JPA来访问数据库

浅浅的花香味﹌ 2022-05-17 01:21 153阅读 0赞

\#            SpringBoot中使用JPA来访问数据库

\#\#1、实体类属性与表字段同名，实现序列化接口

package com.yang.domain;
    
    import java.io.Serializable;
    
    import javax.persistence.Column;
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.Id;
    
    @Entity
    public class Enterprise implements Serializable {
    	
    	private static final long serialVersionUID = 1L;
    
    	@Id
    	@GeneratedValue
    	private Integer id;
    
    	@Column(nullable = false)
    	private String name;
    
    	@Column(nullable = false)
    	private String address;
    
    	public Integer getId() {
    		return id;
    	}
    
    	public void setId(Integer id) {
    		this.id = id;
    	}
    
    	public String getName() {
    		return name;
    	}
    
    	public void setName(String name) {
    		this.name = name == null ? null : name.trim();
    	}
    
    	public String getAddress() {
    		return address;
    	}
    
    	public void setAddress(String address) {
    		this.address = address == null ? null : address.trim();
    	}
    }

\#\#2、实现JpaRepository接口

package com.yang.repo;
    
    import org.springframework.data.jpa.repository.JpaRepository;
    
    import com.yang.domain.Enterprise;
    
    
    /**
     * 继承JpaRepository  接口，实现JPA
     * @author yang
     */
    public interface EnterpriseRepo extends JpaRepository<Enterprise, Integer>{
    	
    	
    }

\#\#3、注入接口

package com.yang.service;
    
    import java.util.List;
    
    import com.yang.domain.Enterprise;
    
    public interface EnterpriseService {
    
    	public void addEnterprise(Enterprise enterprise);
    	public List<Enterprise> getEnterprise();
    }

注入接口，并调用封装好的方法：

package com.yang.service.impl;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    import com.yang.domain.Enterprise;
    import com.yang.repo.EnterpriseRepo;
    import com.yang.service.EnterpriseService;
    
    @Service
    public class EnterpriseServiceImpl implements EnterpriseService{
    
    	@Autowired
    	private EnterpriseRepo enterpriseRepo;
    	
    	@Override
    	public void addEnterprise(Enterprise enterprise) {
    		enterpriseRepo.save(enterprise);
    		
    	}
    
    	@Override
    	public List<Enterprise> getEnterprise() {
    		return enterpriseRepo.findAll();
    	}
    
    }

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