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[英]Get return value (scalar), not result table, from stored procedure using Java and Hibernate
[英]Spring/Hibernate - Get result from Stored procedure without using @Entity in Java
我們在MS SQL中有一個存儲過程,該存儲過程返回的結果集與任何數據庫表都不匹配。 而且我們希望將結果映射到純Java POJO,而不使用@Entity批注。 但是如果我們打電話
entityManager.createStoredProcedureQuery("schema.myProcedure",
PlainPojo.class);
對於org.hibernate.MappingException: Unknown entity
它將失敗org.hibernate.MappingException: Unknown entity
異常
我知道有@SqlResultSetMapping批注,但需要將其放在Entity類上嗎? 這不起作用
@Repository
@SqlResultSetMapping(name = "Mapping")
public class MyRepositoryImpl implements MyRepository
只有這個
@Enity
@SqlResultSetMapping(name = "Mapping")
public class MyEntity
但我們不希望為此使用實體類...因此將其放置在另一個實體上? (不完全是)
還是有可能在代碼中做到?
另一個解決方案?
是否可以制作類似瞬態實體的東西? ->使用@Entity注釋而不創建數據庫表等
我沒有找到關於stackoverflow的復雜解決方案,並且
重新發明了輪子,
也許這對於某些需要在項目中多次調用存儲過程的人有幫助。
主要思想是編寫類似於@StoredProcedure的自定義批注,但獨立於@Entity
@Target(TYPE)
@Retention(RUNTIME)
public @interface CustomNamedStoredProcedureQueries {
/**
* Array of CustomNamedStoredProcedureQuery annotations.
*/
CustomNamedStoredProcedureQuery[] value();
}
@Target(TYPE)
@Retention(RUNTIME)
public @interface CustomNamedStoredProcedureQuery {
/*
* The name of the stored procedure for call.
*/
String name();
/*
* The name of the stored procedure in the database.
*/
String procedureName();
/*
* The scheme name of the database.
*/
String schemeName();
/*
* The name of the package that contains stored procedure in the database.
*/
String packageName();
/*
* Information about all parameters of the stored procedure.
*/
CustomStoredProcedureParameter[] parameters() default {};
/*
* The names of one or more result set mappings, as defined in metadata, when you need custom mapping.
*/
ProcedureRowMapper[] resultSetRowMappers() default {};
/*
* The names of one or more result set mappings, as defined in metadata, when you need 1 to 1 mapping.
*/
ProcedureResultClass[] resultSetMappers() default {};
}
@Target({})
@Retention(RUNTIME)
public @interface CustomStoredProcedureParameter {
/** Name of strored procedure parameter.*/
String name() default "";
/** JDBC type of the parameter.*/
int type();
/** Parameter mode.*/
ParameterMode mode() default ParameterMode.IN;
}
@Target({})
@Retention(RUNTIME)
public @interface ProcedureResultClass {
/* Name of procedure parameter*/
String name();
/* Class of object using for mapping */
Class<?> resultClass();
}
@Target({})
@Retention(RUNTIME)
public @interface ProcedureRowMapper {
/* Name of cursor field for use mapper*/
String name();
/* Class of object using for mapping, must extend BeanPropertyRowMapper */
Class<? extends BeanPropertyRowMapper> mapper();
}
如前所述,當您需要將resultSet 1映射到1時,請使用ProcedureResultClass ,字段必須具有相同的名稱。
當你需要一些自定義映射使用ProcedureRowMapper,你可以@Override mapRow()方法,並手動映射,或者你可以@Override initBeanWrapper(),如果你只需要一些字段轉換的具體方式。
因此,接下來我們需要一種使其起作用的方法。 將其放在應用程序的init方法中,例如main方法的@PostConstruct 。
ProjectUtils {
private JdbcTemplate jdbcTemplate;
@Autowired
public ProjectUtils(DataSource dataSource) {
jdbcTemplate = new JdbcTemplate(DataSource);
}
private static Map<String, SimpleJdbcCall> storedProcedureContainer = new HashMap<>();
public void initStoredProcedure() {
Reflections reflections = new Reflections("my.package");
Set<Class<?>> classList = reflections.getTypesAnnotatedWith(CustomNamedStoredProcedureQueries.class);
for (Class<?> clazz : classList) {
CustomNamedStoredProcedureQueries queriesAnnotation = clazz.getAnnotation(CustomNamedStoredProcedureQueries.class);
for (CustomNamedStoredProcedureQuery queryAnnotation : queriesAnnotation.value()) {
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withSchemaName(queryAnnotation.schemeName())
.withCatalogName(queryAnnotation.packageName())
.withProcedureName(queryAnnotation.procedureName());
Set<SqlParameter> parameters = this.getDeclaredParameters(queryAnnotation.parameters());
jdbcCall.declareParameters(parameters.toArray(new SqlParameter[0]));
Map<String, RowMapper<?>> rowMappers = getDeclaredRowMappers(queryAnnotation.resultSetRowMappers(), queryAnnotation.resultSetMappers());
rowMappers.forEach((parameterName, rowMapper) -> jdbcCall.addDeclaredRowMapper(parameterName, rowMapper));
jdbcCall.compile();
storedProcedureContainer.put(queryAnnotation.name(), jdbcCall);
}
}
}
private Set<SqlParameter> getDeclaredParameters(CustomStoredProcedureParameter[] procedureParameters) {
Set<SqlParameter> parameters = new HashSet<>();
for (CustomStoredProcedureParameter procedureParameter : procedureParameters) {
if (procedureParameter.mode().equals(ParameterMode.IN)) {
parameters.add(new SqlParameter(procedureParameter.name(), procedureParameter.type()));
}
if (procedureParameter.mode().equals(ParameterMode.OUT)) {
parameters.add(new SqlOutParameter(procedureParameter.name(), procedureParameter.type()));
}
}
return parameters;
}
private Map<String, RowMapper<?>> getDeclaredRowMappers(ProcedureRowMapper[] resultSetMappers, ProcedureResultClass[] simpleResultSetMappers) {
Map<String, RowMapper<?>> mappers = new HashMap<>();
if (!ArrayUtils.isEmpty(simpleResultSetMappers)) {
for (ProcedureResultClass procedureResultClass : simpleResultSetMappers) {
mappers.put(procedureResultClass.name(), BeanPropertyRowMapper.newInstance(procedureResultClass.resultClass()));
}
return mappers;
}
try {
for (ProcedureRowMapper resultSetMapper : resultSetMappers) {
mappers.put(resultSetMapper.name(), resultSetMapper.mapper().newInstance());
}
} catch (InstantiationException | IllegalAccessException e) {
e.printStackTrace();
}
return mappers;
}
public SimpleJdbcCall getProcedure(String name) {
return storedProcedureContainer.get(name);
}
}
示例 (我使用oracledb,但稍作更改便可以用於另一個db)
@CustomNamedStoredProcedureQueries({
@CustomNamedStoredProcedureQuery(
name = "getFoo",
schemeName = "FooScheme",
packageName = "FooPackage",
procedureName = "get_Foo",
resultSetMappers = @ProcedureResultClass(name = "foo_cursor", resultClass = Foo.class),
parameters = {
@CustomStoredProcedureParameter(name = "foo_id", type = OracleTypes.NUMBER, mode = ParameterMode.IN),
@CustomStoredProcedureParameter(name = "error_code", type = OracleTypes.NUMBER, mode = ParameterMode.OUT),
@CustomStoredProcedureParameter(name = "foo_cursor", type = OracleTypes.CURSOR, mode = ParameterMode.OUT),
}
),
@CustomNamedStoredProcedureQuery(
name = "deleteFoo",
schemeName = "FooScheme",
packageName = "FooPackage",
procedureName = "delete_Foo",
parameters = {
@CustomStoredProcedureParameter(name = "foo_id", type = OracleTypes.NUMBER, mode = ParameterMode.IN),
@CustomStoredProcedureParameter(name = "error_code", type = OracleTypes.NUMBER, mode = ParameterMode.OUT),
}
)
})
public class Foo {
long id;
String name;
int age;
public void setId(long id) {
this.id= id;
}
public long getId() {
return this.id;
}
public void setName(String name) {
this.name = name;
}
public String getName() {
return this.name;
}
public void setAge(int age) {
this.age = age;
}
public int getAge() {
return this.age;
}
}
稱它為:
public Foo getFoo(Long fooId) {
SqlParameterSource sqlParams = new MapSqlParameterSource()
.addValue("foo_id", fooId);
SimpleJdbcCall procedure = projectUtils.getProcedure("getFoo");
Map<String, Object> result = procedure.execute(sqlParams);
return ((List<Foo>) result.get("foo_cursor")).get(0);
}
提示 -可以將其與自定義類型(存儲在bd中的類型)一起使用,例如Array ,因為您需要創建自定義類型的AbstractSqlTypeValue擴展並覆蓋createTypeValue() ,然后像其他參數一樣傳遞它( 僅在oracle上經過仔細測試 )。
必須在方案級別和更高級別上聲明CustomType,在程序包級別上聲明它不起作用,必須以大寫形式調用方案和類型。
@Override
protected Object createTypeValue(Connection connection, int sqlType, String typeName) throws SQLException {
if (connection.isWrapperFor(OracleConnection.class)) {
OracleConnection oracleConnection = connection.unwrap(OracleConnection.class);
return oracleConnection.createARRAY("FOOSCHEME.NUMBERARRAY", this.array); // array pass when customType class init
}
return connection.createArrayOf("FOOSCHEME.NUMBERARRAY", this.array);
}
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