將數組從Java傳遞到PLSQL存儲過程

Question

我試圖將Java數組傳遞給PLSQL存儲過程，但是當我嘗試執行時，我得到以下異常

java.sql.SQLException: Inconsistent java and sql object types

我的DAO類代碼片段

List projectList = new ArrayList();

public void saveRecord(List<Project> project) 
                       throws DatabaseException,SQLException {

    for (Project items: project) {
        insertRecord(items);
    }
}

private void insertRecord(Project project) throws SQLException {
    projectList.add(project);

callablestatement = 
         (OracleCallableStatement)connection.prepareCall("{call my_proc(?)}");

Object[] project1 = projectList.toArray();

StructDescriptor projectTypeDesc = StructDescriptor.createDescriptor("MY_TYPE",
conn);

STRUCT structProject1 = new STRUCT(projectTypeDesc, 
connection, project);

STRUCT[] structArrayOfProjects = {structProject1};

 ArrayDescriptor projectTypeArrayDesc = ArrayDescriptor.createDescriptor
("MY_ARRAY", connection); 

ARRAY arrayOfProjects = new ARRAY(projectTypeArrayDesc, connection,
structArrayOfProjects);// error in this line

callablestatement.setArray(1, arrayOfProjects);  

我該如何解決這個問題？

編輯1

如果我這樣做

Object[] project1 = new Object[]{project.getProjectId(), project.getProjectTitle()};

然后沒有錯誤和記錄插入表中。

但是如果我願意的話

Object[] project1 = projectList.toArray();

然后異常拋出Inconsistent java and sql object types

Answer 1

正如我在其他線程中已經說過的那樣，在分配整個Project對象數組時，必須將Project對象的字段分配給Object數組。 你可以做你想要的，但是，正如我在另一個線程中已經說過的那樣，你必須循環遍歷項目列表並為列表中的每個元素創建一個STRUCT對象，保存每個項目的字段：

StructDescriptor projectTypeDesc = StructDescriptor.createDescriptor("MY_TYPE",
connection);

// array holding structs, where each struct is based on an array
//   with fields of Project object
STRUCT[] projectsAsStructs = new STRUCT[projectList.size()];

// for each Project object, create a STRUCT object containing its fields
for (int i = 0; i < projectList.size(); ++i) {
  Project project = projectList.get(i);

  Object[] projectFields = new Object[] {project.getProjectId(),
                                         project.getProjectTitle()};

  STRUCT projectStruct = new STRUCT(projectTypeDesc,
                                    connection, projectFields);

  projectsAsStructs[i] = projectStruct;
}

// now you have all your Project objects ready to be saved in one go:
ArrayDescriptor projectTypeArrayDesc = ArrayDescriptor.createDescriptor
("MY_ARRAY", connection); 

ARRAY arrayOfProjects = new ARRAY(projectTypeArrayDesc, connection,
                                  projectsAsStructs);

callablestatement.setArray(1, arrayOfProjects);