warpdb

DSL-driven RDBMS interface for Java:

Status:

Design principles

• JPA-annotation based configuration.
• DSL-style API reads like English.
• Support raw SQL for very complex query.
• No "attach/dettach".
• All entities are simple POJOs without proxy-ing.

Database Support

• MySQL 5.x/8.x

Configuration

Maven dependency:

<dependency>
    <groupId>com.itranswarp</groupId>
    <artifactId>warpdb</artifactId>
    <version>${warpdb.version}</version>
</dependency>

Use 5.x for Spring 5.x and 6.x for Spring 6.x.

Warpdb is built on top of Spring-JDBC. JdbcTemplate or DataSource is required when build warpdb instance:

<bean class="com.itranswarp.warpdb.WarpDb" init-method="init">
    <property name="basePackages">
        <list>
            <value>com.test.product.model</value>
            <value>com.test.order.model</value>
        </list>
    </property>
    <property name="jdbcTemplate" ref="jdbcTemplate" />
</bean>

Or using data source:

<bean class="com.itranswarp.warpdb.WarpDb" init-method="init">
    <property name="basePackages">
        <list>
            <value>com.test.product.model</value>
            <value>com.test.order.model</value>
        </list>
    </property>
    <property name="dataSource" ref="dataSource" />
</bean>

Basic Usage

Fully JPA Annotation Support

Entities are configured with JPA annotation:

@Entity
@Table(name="user")
public class User {
    @Id
    String id;

    @Column(nullable=false)
    String name;
}

Query

Query by primary key:

// get user, or throw EntityNotFoundException if not found:
User user = warpdb.get(User.class, "123");

// get user, or return null if not found:
User another = warpdb.fetch(User.class, "456");

You have to provide multiple values if multiple id columns are defined:

Product p = warpdb.get(Product.class, "p123", "c456);

Warpdb supports criteria query and raw SQL query, both are type-safe:

List<User> users = warpdb.from(User.class)
        .where("name=?", "bob")
        .orderBy("updatedAt").desc()
        .list();

Get first result or null if not found:

User user = warpdb.from(User.class)
        .where("name=?", "bob")
        .orderBy("updatedAt").desc()
        .first();

Query for update:

User user = warpdb.selectForUpdate()
        .where("id=?", 123)
        .first();

Using raw SQL:

List<User> users = warpdb.query("select * from User order by name limit 100");

Paged Query

Warpdb supports paged query by specify page index and page size:

// page 3, 10 items per page:
PagedResults<User> pr = warpdb.from(User.class)
        .orderBy("updatedAt")
        .list(3, 10);
System.out.println(pr.page.pageIndex); // 3
System.out.println(pr.page.itemsPerPage); // 10
System.out.println(pr.page.totalPages); // 92
System.out.println(pr.page.totalItems); // 912
List<User> list = pr.results; // current page items

A paged query will generate 2 SQLs when execute list(pageIndex, pageSize):

SELECT COUNT(*) FROM User;
SELECT * FROM User ORDER BY updatedAt limit 20, 10

Insert

Using insert() to insert one or more entities:

User user = new User();
user.setId(...);
user.setName(...);
Product product = new Product();
product.setId(...);
product.setName(...);
warpdb.insert(user, product);

Batch insert

Using insert(List<T>) to do batch save entities.

Update

Using update() to update one or more entities:

User user = ...
user.setName(...);
Product product = ...
product.setName(...);
warpdb.update(user, product);

Batch update

Using update(List<T>) to do batch update entities.

Remove

Using remove() to remove one or more entities:

User user = ...
Product product = ...
warpdb.remove(user, product);

Batch remove

Using remove(List<T>) to do batch remove entities.

Misc

Enum Support

Enum is stored as VARCHAR(50) in database:

@Entity
public class User {
    RoleEnum role;
}

Attribute Converter

Values used in Java and db can be converted by attribute converter:

@Entity
public class User {
    // stored as "DATE" in db:
    @Convert(converter = LocalDateConverter.class)
    @Column(columnDefinition = "date")
    public LocalDate birth;
}

Listeners

Listeners must be added as entity method with annotation PostLoad, PrePersist, PostPersist, PreUpdate, PostUpdate, PreRemove, PostRemove:

@Entity
public class User {
    @Id
    String id;

    long createdAt;

    @PrePersist()
    public void prePersist() {
        if (this.id == null) {
            this.id = nextId();
        }
        this.createdAt = System.currentTimeMillis();
    }
}

Schema Export

Using getDDL() to export schema:

String ddl = warpdb.getDDL();

or get schema for one entity:

String ddl = warpdb.getDDL(User.class);