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Unary JPA Operators

I want to know if it is possible to set a boolean value in JPA using the Unary Operator. I mean something like this

@Modifying
@Query("update Computer com set com.enabled=!com.enabled where com.id = ?1")

Allowed field is displayed this way in POJO

private Boolean enabled;

public Boolean getEnabled() {
    return enabled;
}

public void setEnabled(Boolean enabled) {
    this.enabled = enabled;
}

stored in the database as boolean(1)

this is the result

Caused by: java.lang.IllegalArgumentException: org.hibernate.QueryException: expecting '=', found 'c' [update com.nicinc.Computer com set com.enabled=!com.enabled where com.id = ?1]

and here the JPA properties

Spring JPA Data Properties

spring.datasource.url=jdbc:h2:mem:testdb;MODE=MySQL;DB_CLOSE_ON_EXIT=FALSE
spring.datasource.username=sa
spring.datasource.password=
spring.jpa.show-sql=false
spring.jpa.properties.hibernate.format_sql=true
hibernate.dialect=org.hibernate.dialect.H2Dialect
+3


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2 answers


Different databases have different support for handling boolean expressions, so there isn't enough room for JPA to provide a generic approach, so you must be explicit:



update Computer
set enabled = case when enabled = true then false else true end
where id = ?1
+2


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You are probably using tinyint

MySQL side for this column and the persistence provider cannot distinguish between 0

and 1

how false

or true

.

If you are using JPA 2.1

, I would suggest creating a global boolean converter:

@Converter(autoApply=true)
public class GlobalBooleanConverter implements AttributeConverter<Boolean, Integer>{
    @Override
    public String convertToDatabaseColumn(Boolean value) {
        if (Boolean.TRUE.equals(value)) {
            return Integer.valueOf(1);
        } else {
            return Integer.valueOf(0);
        }
    }
    @Override
    public Boolean convertToEntityAttribute(String value) {
        return Integer.valueOf(1).equals(value);
    }
}


An alternative to selection could be to change the POJO field to Integer and change the query like this:

@Modifying
@Query("update Computer com set com.enabled=((-com.enabled)+1) where com.id = ?1")
0


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