HarmonyOS 基础数据库

1.配置

2.使用

一 配置

javapoet_java.jar  

orm_annotations_java.jar

orm_annotations_processor_java.jar

这三个包拷贝到项目libs目录后配置2个地方。

compileOptions {
    annotationEnabled true
}

compile files(
        "./libs/javapoet_java.jar",
        "./libs/orm_annotations_java.jar",
        "./libs/orm_annotations_processor_java.jar"
)
annotationProcessor files(
        "./libs/javapoet_java.jar",
        "./libs/orm_annotations_java.jar",
        "./libs/orm_annotations_processor_java.jar"
)

二 使用

1.新增

2.更新

3.删除

4.查询

package com.example.demo2.data;

public class Student {
    int id;
    String name;
    int age;
    double salary;

    public Student() {
    }

    public Student(int id, String name, int age, double salary) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.salary = salary;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                ", salary=" + salary +
                '}';
    }
}

package com.example.demo2.utils;

import com.example.demo2.data.Student;
import ohos.app.Context;
import ohos.data.DatabaseHelper;
import ohos.data.rdb.*;
import ohos.data.resultset.ResultSet;

import java.util.ArrayList;
import java.util.List;

public class DBUtils {
    private RdbStore rdbStore;
    private DatabaseHelper databaseHelper;

    public DBUtils(Context context) {
        databaseHelper = new DatabaseHelper(context);
        initDB();
    }

    private void initDB() {
        StoreConfig storeConfig = StoreConfig.newDefaultConfig("school.db");

        rdbStore = databaseHelper.getRdbStore(storeConfig, 1, new RdbOpenCallback() {
            @Override
            public void onCreate(RdbStore rdbStore) {
                rdbStore.executeSql("create table if not exists " +
                        "student(id integer primary key autoincrement," +
                        "name text not null,age integer,salary real)");
            }

            @Override
            public void onUpgrade(RdbStore rdbStore, int i, int i1) {

            }
        });
    }

    public boolean insertStudent(Student student) {
        ValuesBucket valuesBucket = new ValuesBucket();
        valuesBucket.putInteger("age", student.getAge());
        valuesBucket.putString("name", student.getName());
        valuesBucket.putDouble("salary", student.getSalary());

        long insert = rdbStore.insert("student", valuesBucket);
        return insert > 0 ? true : false;
    }

    public boolean updateStudent(Student student) {
        ValuesBucket valuesBucket = new ValuesBucket();
        valuesBucket.putInteger("age", student.getAge());
        valuesBucket.putString("name", student.getName());
        valuesBucket.putDouble("salary", student.getSalary());

        RdbPredicates rdbPredicates = new RdbPredicates("student");
        rdbPredicates.equalTo("id", student.getId());

        int t = rdbStore.update(valuesBucket, rdbPredicates);

        return t > 0 ? true : false;
    }

    public boolean deleteStudent(Student student) {
        RdbPredicates rdbPredicates = new RdbPredicates("student");
        rdbPredicates.equalTo("id", student.getId());

        int t = rdbStore.delete(rdbPredicates);

        return t > 0 ? true : false;
    }

    public Student queryById(int id) {
        Student student = new Student();
        RdbPredicates rdbPredicates = new RdbPredicates("student");
        rdbPredicates.equalTo("id", id);
        ResultSet query = rdbStore.query(rdbPredicates, new String[]{"id", "name", "age", "salary"});
        while (query.goToNextRow()) {
            student.setId(query.getInt(query.getColumnIndexForName("id")));
            student.setName(query.getString(query.getColumnIndexForName("name")));
            student.setAge(query.getInt(query.getColumnIndexForName("age")));
            student.setSalary(query.getDouble(query.getColumnIndexForName("salary")));
        }

        return student;
    }

    public List<Student> queryList(String name) {
        List<Student> list = new ArrayList<Student>();
        RdbPredicates rdbPredicates = new RdbPredicates("student");
        rdbPredicates.like("name", name);
        ResultSet query = rdbStore.query(rdbPredicates, new String[]{"id", "name", "age", "salary"});
        while (query.goToNextRow()) {
            Student student = new Student();
            student.setId(query.getInt(query.getColumnIndexForName("id")));
            student.setName(query.getString(query.getColumnIndexForName("name")));
            student.setAge(query.getInt(query.getColumnIndexForName("age")));
            student.setSalary(query.getDouble(query.getColumnIndexForName("salary")));
            list.add(student);
        }

        return list;
    }
}

package com.example.demo2.slice;

import com.example.demo2.ResourceTable;
import com.example.demo2.data.Student;
import com.example.demo2.utils.DBUtils;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Button;
import ohos.agp.components.Component;
import ohos.hiviewdfx.HiLog;
import ohos.hiviewdfx.HiLogLabel;

import java.util.List;

public class DBTestSlice extends AbilitySlice {
    private final HiLogLabel hiLogLabel = new HiLogLabel(HiLog.LOG_APP, 1, "DBTestSlice");

    @Override
    protected void onStart(Intent intent) {
        super.onStart(intent);
        super.setUIContent(ResourceTable.Layout_db_test);

        Button add = (Button) findComponentById(ResourceTable.Id_btnAdd);
        Button update = (Button) findComponentById(ResourceTable.Id_btnUpdate);
        Button delete = (Button) findComponentById(ResourceTable.Id_btnDelete);
        Button one = (Button) findComponentById(ResourceTable.Id_btnQueryById);
        Button list = (Button) findComponentById(ResourceTable.Id_btnQueryAll);
        add.setClickedListener(this::onClick);
        update.setClickedListener(this::onClick);
        delete.setClickedListener(this::onClick);
        one.setClickedListener(this::onClick);
        list.setClickedListener(this::onClick);
    }

    private void onClick(Component component) {
        if (component.getId() == ResourceTable.Id_btnAdd) {
            try {
                for (int i = 0; i < 10; i++) {
                    Student student = new Student(i, "jack", 30 + i, 12000);

                    boolean b = new DBUtils(DBTestSlice.this).insertStudent(student);
                    if (b) {
                        HiLog.info(hiLogLabel, "---插入成功-----" + i);
                    }
                }

            } catch (Exception e) {
                HiLog.info(hiLogLabel, "---插入失败-----" + e.getMessage());
            }
        }
        if (component.getId() == ResourceTable.Id_btnQueryById) {
            try {
                Student student = new DBUtils(DBTestSlice.this).queryById(0);

                HiLog.info(hiLogLabel, "---查询1条成功-----");
                HiLog.info(hiLogLabel, student.getName());
            } catch (Exception e) {
                HiLog.info(hiLogLabel, "---查询1条失败-----" + e.getMessage());
            }
        }
        if (component.getId() == ResourceTable.Id_btnQueryAll) {
            try {
                List<Student> list = new DBUtils(DBTestSlice.this).queryList("jack");
                HiLog.info(hiLogLabel, "---查询全部：size-----" + list.size());
                for (int i = 0; i < list.size(); i++) {
                    HiLog.info(hiLogLabel, list.get(i).toString());
                }
                HiLog.info(hiLogLabel, "---查询全部成功-----");

            } catch (Exception e) {
                HiLog.info(hiLogLabel, "---查询全部失败-----" + e.getMessage());
            }
        }
    }

    @Override
    protected void onActive() {
        super.onActive();
    }

    @Override
    protected void onForeground(Intent intent) {
        super.onForeground(intent);
    }
}

<?xml version="1.0" encoding="utf-8"?>
<DirectionalLayout
    xmlns:ohos="http://schemas.huawei.com/res/ohos"
    ohos:height="match_parent"
    ohos:width="match_parent"
    ohos:alignment="center"
    ohos:orientation="vertical">

    <Button
        ohos:id="$+id:btnAdd"
        ohos:height="50vp"
        ohos:width="200vp"
        ohos:background_element="$graphic:background_button"
        ohos:text="新增1条数据"
        ohos:text_color="#FFFFFF"
        ohos:text_size="20fp"
        ohos:top_margin="20vp">
    </Button>

    <Button
        ohos:id="$+id:btnDelete"
        ohos:height="50vp"
        ohos:width="200vp"
        ohos:background_element="$graphic:background_button"
        ohos:text="删除1条数据"
        ohos:text_color="#FFFFFF"
        ohos:text_size="20fp"
        ohos:top_margin="20vp">
    </Button>

    <Button
        ohos:id="$+id:btnUpdate"
        ohos:height="50vp"
        ohos:width="200vp"
        ohos:background_element="$graphic:background_button"
        ohos:text="更新1条数据"
        ohos:text_color="#FFFFFF"
        ohos:text_size="20fp"
        ohos:top_margin="20vp">
    </Button>

    <Button
        ohos:id="$+id:btnQueryById"
        ohos:height="50vp"
        ohos:width="200vp"
        ohos:background_element="$graphic:background_button"
        ohos:text="查询1条数据"
        ohos:text_color="#FFFFFF"
        ohos:text_size="20fp"
        ohos:top_margin="20vp">
    </Button>

    <Button
        ohos:id="$+id:btnQueryAll"
        ohos:height="50vp"
        ohos:width="200vp"
        ohos:background_element="$graphic:background_button"
        ohos:text="查询全部数据"
        ohos:text_color="#FFFFFF"
        ohos:text_size="20fp"
        ohos:top_margin="20vp">
    </Button>
</DirectionalLayout>