我有这个代码:
long userID = user.getId();
String query = "select userclient.username from twitter_content.userclient where userclient.userid = " +
"(select follower.followerid from twitter_content.follower where follower.followerid = userclient.userid and follower.userid = "+userID+")";
我想在 Where 子句中使用 userID 作为查询的一部分,但我似乎没有正确连接 userID(我希望它被读取为动态值,而不是字符串)。有人可以提供一些指导吗它?
编辑:
这是完整的源代码:
public ArrayList<Post> retrieveFollowerDB(String userName){
ArrayList<Post> postArray = new ArrayList<Post>();
ArrayList<Integer> intArray = new ArrayList<Integer>();
ResultSet rs = null;
Connection conn = null;
PreparedStatement pstmt = null;
Twitter twitter = new TwitterFactory().getInstance();
try {
User user = twitter.showUser(userName);
long userID = user.getId();
} catch (IllegalStateException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (TwitterException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
String query = "select userclient.username from twitter_content.userclient where userclient.userid = " +
"(select follower.followerid from twitter_content.follower where follower.followerid = userclient.userid and follower.userid = ?)";
System.out.println(query);
String userNames = null;
String query1 = null;
try{
JDBC db = new JDBC();
conn = db.getConnection();
pstmt = conn.prepareStatement(query);
pstmt.setLong(1, userID);
rs = pstmt.executeQuery();
Properties config = new Properties();
config.load(new FileInputStream("C:/Users/L31207/Desktop/FYPJ/OpenCalais/MarcusFYPJ/categories.properties"));
String[][] categories = fetchArrayFromPropFile("content", config);
HashMap<String,Integer> hashmap = new HashMap<String,Integer>();
for (String[] mapping : categories)
{
hashmap.put(mapping[0], 0);
}
while(rs.next()){
int id = rs.getInt("followerid");
userNames = rs.getString("username");
intArray.add(id);
}
ResultSet rs1 = null;
Connection conn1 = null;
PreparedStatement pstmt1 = null;
for(int i=0;i<intArray.size();i++){
query1 = "Select post.content from twitter_content.post where post.userid = "+intArray.get(i)+"";
JDBC db1 = new JDBC();
conn1 = db1.getConnection();
pstmt1 = conn1.prepareStatement(query1);
rs1 = pstmt1.executeQuery();
}
while(rs1.next()){
Post post = new Post(rs.getString(userNames), rs.getString("content"), hashmap);
System.out.println(rs.getString("content"));
postArray.add(post);
System.out.println(postArray.size());
}
}
catch (Exception e) {
System.err.println(e);
}
return postArray;
}