springboot jpa创建表自动添加注释

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE, ElementType.METHOD, ElementType.FIELD})
public @interface Comment {
    String value() default "";
}

package cn.com.micro.qx.comment;

import org.hibernate.boot.Metadata;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.integrator.spi.Integrator;
import org.hibernate.mapping.PersistentClass;
import org.hibernate.mapping.Property;
import org.hibernate.service.spi.SessionFactoryServiceRegistry;
import org.springframework.stereotype.Component;

import java.lang.reflect.Field;
import java.util.Iterator;


@Component
public class CommentIntegrator implements Integrator {
    public static final CommentIntegrator INSTANCE = new CommentIntegrator();

    public CommentIntegrator() {
        super();
    }

    /**
     * Perform comment integration.
     *
     * @param metadata        The "compiled" representation of the mapping information
     * @param sessionFactory  The session factory being created
     * @param serviceRegistry The session factory's service registry
     */
    @Override
    public void integrate(Metadata metadata, SessionFactoryImplementor sessionFactory, SessionFactoryServiceRegistry serviceRegistry) {
        processComment(metadata);
    }

    /**
     * Not used.
     *
     * @param sessionFactoryImplementor     The session factory being closed.
     * @param sessionFactoryServiceRegistry That session factory's service registry
     */
    @Override
    public void disintegrate(SessionFactoryImplementor sessionFactoryImplementor, SessionFactoryServiceRegistry sessionFactoryServiceRegistry) {
    }

    /**
     * Process comment annotation.
     *
     * @param metadata process annotation of this {@code Metadata}.
     */
    private void processComment(Metadata metadata) {
        for (PersistentClass persistentClass : metadata.getEntityBindings()) {
            // Process the Comment annotation is applied to Class
            Class<?> clz = persistentClass.getMappedClass();
            if (clz.isAnnotationPresent(Comment.class)) {
                Comment comment = clz.getAnnotation(Comment.class);
                persistentClass.getTable().setComment(comment.value());
            }

            // Process Comment annotations of identifier.
            Property identifierProperty = persistentClass.getIdentifierProperty();
            if (identifierProperty != null) {
                fieldComment(persistentClass, identifierProperty.getName());
            } else {
                org.hibernate.mapping.Component component = persistentClass.getIdentifierMapper();
                if (component != null) {
                    //noinspection unchecked
                    Iterator<Property> iterator = component.getPropertyIterator();
                    while (iterator.hasNext()) {
                        fieldComment(persistentClass, iterator.next().getName());
                    }
                }
            }
            // Process fields with Comment annotation.
            //noinspection unchecked
            Iterator<Property> iterator = persistentClass.getPropertyIterator();
            while (iterator.hasNext()) {
                fieldComment(persistentClass, iterator.next().getName());
            }
        }
    }

    /**
     * Process @{code comment} annotation of field.
     *
     * @param persistentClass Hibernate {@code PersistentClass}
     * @param columnName            name of field
     */
    private void fieldComment(PersistentClass persistentClass, String columnName) {
        try {
            Field field = persistentClass.getMappedClass().getDeclaredField(columnName);
            if (field.isAnnotationPresent(Comment.class)) {
                String comment = field.getAnnotation(Comment.class).value();
                String sqlColumnName= persistentClass.getProperty(columnName).getValue().getColumnIterator().next().getText();
                Iterator<org.hibernate.mapping.Column> columnIterator = persistentClass.getTable().getColumnIterator();
                while (columnIterator.hasNext()) {
                    org.hibernate.mapping.Column column = columnIterator.next();
                    if (sqlColumnName.equalsIgnoreCase(column.getName())) {
                        column.setComment(comment);
                        break;
                    }
                }
            }
        } catch (NoSuchFieldException | SecurityException ignored) {
        }
    }
}

package cn.com.micro.qx.config;

import cn.com.geoscene.micro.qx.comment.CommentIntegrator;
import org.hibernate.jpa.boot.spi.IntegratorProvider;
import org.springframework.boot.autoconfigure.orm.jpa.HibernatePropertiesCustomizer;
import org.springframework.stereotype.Component;

import java.util.Collections;
import java.util.Map;


@Component
public class HibernateConfig implements HibernatePropertiesCustomizer {
    @Override
    public void customize(Map<String, Object> hibernateProperties) {
        hibernateProperties.put("hibernate.use_sql_comments", true);
        hibernateProperties.put("hibernate.integrator_provider",
                (IntegratorProvider) () -> Collections.singletonList(CommentIntegrator.INSTANCE));
    }
}

package cn.com.micro.qx.entity;

import cn.afterturn.easypoi.excel.annotation.Excel;
import cn.com.geoscene.micro.qx.comment.Comment;
import com.fasterxml.jackson.annotation.JsonFormat;
import com.fasterxml.jackson.annotation.JsonProperty;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import org.hibernate.annotations.ColumnTransformer;
import org.hibernate.validator.constraints.Length;
import org.springframework.data.jpa.domain.support.AuditingEntityListener;

import javax.persistence.*;
import java.io.Serializable;
import java.util.Date;

@Entity
@Table(name = "XQYL", schema = "sde")
@EntityListeners(AuditingEntityListener.class)
@Data
@ApiModel(description = "院落单元信息")
@Comment("院落单元信息")
public class CellUnit implements Serializable {

    @Id
    @JsonProperty("objectid")
    @ApiModelProperty(value = "主键")
    @Comment("主键")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long objectid;

    @Length(max = 20)
    @Excel(name = "XQYLDM")
    @JsonProperty("XQYLDM")
    @Column(name = "XQYLDM",length = 20)
    @Comment("小区院落代码")
    @ApiModelProperty(value = "小区院落代码")
    String XQYLDM;

    @Length(max = 100)
    @Excel(name = "XQYLMC")
    @JsonProperty("XQYLMC")
    @Column(name = "XQYLMC",length = 100)
    @Comment("小区院落名称")
    @ApiModelProperty(value = "小区院落名称")
    String XQYLMC;

    
}

 当postgres数据库的schema和table名称都是大写的时候，在

CommentIntegrator里面使用这个代码。问题是使用这个代码会报异常数据库超过连接数。暂时还没有想到办法解决。还有一个问题是，使用下面这个代码要先屏蔽下面的代码，执行程序先创建好了表，才能在重新运行程序执行添加注释的功能

 private void processComment2(Metadata metadata, SessionFactoryImplementor sessionFactory) {

        for (PersistentClass persistentClass : metadata.getEntityBindings()) {
            Class<?> clz = persistentClass.getMappedClass();
            String tableName = persistentClass.getTable().getName().toUpperCase();
            System.out.println("-----------table " + tableName);
            try {
                String schema = persistentClass.getTable().getSchema().toUpperCase();
                if (clz.isAnnotationPresent(Comment.class)) {
                    Comment comment = clz.getAnnotation(Comment.class);
                    String value = comment.value();
                    if (StringUtils.isNotBlank(value)) {
                        String sql = String.format(
                                "COMMENT ON TABLE \"%s\".\"%s\" IS '%s'", schema, tableName, value);
                        try {
                            sessionFactory.getServiceRegistry().getService(ConnectionProvider.class)
                                    .getConnection().createStatement().execute(sql);
                        } catch (SQLException e) {
                            e.printStackTrace();
                        }
                    }
                }

                Property identifierProperty = persistentClass.getIdentifierProperty();
                if (identifierProperty != null) {
                    fieldComment(persistentClass, identifierProperty.getName(), sessionFactory);
                } else {
                    org.hibernate.mapping.Component component = persistentClass.getIdentifierMapper();
                    if (component != null) {
                        Iterator<Property> iterator = component.getPropertyIterator();
                        while (iterator.hasNext()) {
                            fieldComment(persistentClass, iterator.next().getName(), sessionFactory);
                        }
                    }
                }
                Iterator<Property> iterator = persistentClass.getPropertyIterator();
                while (iterator.hasNext()) {
                    fieldComment(persistentClass, iterator.next().getName(), sessionFactory);
                }
//                sessionFactory.close();
            }catch (Exception e){
                e.printStackTrace();
            }

        }


    }