Java 无法将sql（jpa查询）返回的列转换为自定义类

有人问过这个问题，但我无法解决我的问题

上一个问题：

在我的项目中，我有一个自定义类，定义如下：

public class VerticalBarChartDomain {

    private String name;
    private Long value;
    // constructors
    public VerticalBarChartDomain() {
        // TODO Auto-generated constructor stub
    }
    public VerticalBarChartDomain(String name, Long value) {
        super();
        this.name = name;
        this.value = value;
    }
    //getters and setters
    public String getName() {
        return name;
    }
    public Long getValue() {
        return value;
    }
    public void setName(String name) {
        this.name = name;
    }
    public void setValue(Long value) {
        this.value = value;
    }

}

@Query(value="select   new in.net.rserver.domain.VerticalBarChartDomain( DATE(r.start_time), count(distinct(r.ride_id)) ) from ride r where  r.start_time >= date_sub(curdate(), interval 6 day) group by DATE(r.start_time)",nativeQuery=true)
    public List<VerticalBarChartDomain> getRidesPerDayForVBChart();

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '.net.yaana.server.rserver.domain.VerticalBarChartDomain(DATE(r.start_time), coun' at line 1
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:na]
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488) ~[na:na]
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.Util.getInstance(Util.java:408) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:943) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2527) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2680) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2494) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1858) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1966) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]

在JPA存储库中，我有一个查询，如下所示

public class VerticalBarChartDomain {

    private String name;
    private Long value;
    // constructors
    public VerticalBarChartDomain() {
        // TODO Auto-generated constructor stub
    }
    public VerticalBarChartDomain(String name, Long value) {
        super();
        this.name = name;
        this.value = value;
    }
    //getters and setters
    public String getName() {
        return name;
    }
    public Long getValue() {
        return value;
    }
    public void setName(String name) {
        this.name = name;
    }
    public void setValue(Long value) {
        this.value = value;
    }

}

@Query(value="select   new in.net.rserver.domain.VerticalBarChartDomain( DATE(r.start_time), count(distinct(r.ride_id)) ) from ride r where  r.start_time >= date_sub(curdate(), interval 6 day) group by DATE(r.start_time)",nativeQuery=true)
    public List<VerticalBarChartDomain> getRidesPerDayForVBChart();

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '.net.yaana.server.rserver.domain.VerticalBarChartDomain(DATE(r.start_time), coun' at line 1
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:na]
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:488) ~[na:na]
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.Util.getInstance(Util.java:408) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:943) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2527) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2680) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2494) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1858) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1966) ~[mysql-connector-java-5.1.43.jar:5.1.43]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]

---

请纠正我的错误。

好吧，这应该是SQL。和.net.rserver.domain.VerticalBarChartDomain（…）中的新的

，

不是有效的SQL。它将是有效的JPQL，但JPQL与SQL语言不同，查询的其余部分不是有效的JPQL。简而言之，你在写java中的一半，剩下的C++。没有什么能执行这样的事情。只需返回两列，遍历查询将返回的列表，并将每个对象数组转换为VerticalBarChartDomain的一个实例。@JBNizet，感谢您告知我的错误，您能告诉我如何访问对象的列吗？我不知道您的意思。假设查询返回，#ride_date，rides'2018-06-14'，15''2018-06-15'，40''2018-06-16'，53''2018-06-17'，74''2018-06-18'，31'，在对象[]列表中，如何从ObjectWell行[0]中获取每一列是该行的第一个元素，而行[1]是第二个元素。这是一个数组。它与所有其他阵列一样工作。