spring可以方便的访问oracle的存储过程、函数

spring文档举了一个访问sysdate的例子，它不需要输入参数，使用如下：

public class TestStoredProcedure {

public static void main(String[] args) {
TestStoredProcedure t = new TestStoredProcedure();
t.test();
System.out.println("Done!");
}

void test() {
DriverManagerDataSource ds = new DriverManagerDataSource();
ds.setDriverClassName("oracle.jdbc.OracleDriver");
ds.setUrl("jdbc:oracle:thin:@localhost:1521:mydb");
ds.setUsername("scott");
ds.setPassword("tiger");

MyStoredProcedure sproc = new MyStoredProcedure(ds);
Map results = sproc.execute();
printMap(results);
}

private class MyStoredProcedure extends StoredProcedure {

private static final String SQL = "sysdate";

public MyStoredProcedure(DataSource ds) {
setDataSource(ds);
setFunction(true);
setSql(SQL);
declareParameter(new SqlOutParameter("date", Types.DATE));
compile();
}

public Map execute() {
// the 'sysdate' sproc has no input parameters, so an empty Map is supplied...
return execute(new HashMap());
}
}

private static void printMap(Map results) {
for (Iterator it = results.entrySet().iterator(); it.hasNext(); ) {
System.out.println(it.next());
}
}
}

但是如果访问带输入参数的function怎么办？很简单，只是要注意，输出参数的声明一定要放在输入参数声明的前面。否则，返回值永为null

如下：

public class TestStoredProcedure {

public static void main(String[] args) {
TestStoredProcedure t = new TestStoredProcedure();
t.test();
System.out.println("Done!");
}

void test() {
DriverManagerDataSource ds = new DriverManagerDataSource();
ds.setDriverClassName("oracle.jdbc.OracleDriver");
ds.setUrl("jdbc:oracle:thin:@localhost:1521:mydb");
ds.setUsername("scott");
ds.setPassword("tiger");

MyStoredProcedure sproc = new MyStoredProcedure(ds);
Map results = sproc.execute();
printMap(results);
}

private class MyStoredProcedure extends StoredProcedure {

private static final String SQL = "youfunc";

public MyStoredProcedure(DataSource ds) {
setDataSource(ds);
setFunction(true);
setSql(SQL);

//一定要注意顺序，将OUt放在前面，否则，你的返回值永远为null

declareParameter(new SqlOutParameter("myrt", Types.varchar));
declareParameter(new SqlParameter("pIN", Types.varchar)); compile();
}

public Map execute() {
// the 'sysdate' sproc has no input parameters, so an empty Map is supplied...

Map m=new HashMap();

m.put("PIn","test");
return execute(new HashMap());
}
}

private static void printMap(Map results) {
for (Iterator it = results.entrySet().iterator(); it.hasNext(); ) {
System.out.println(it.next());
}
}
}