我正在尝试为 android 上的 SQlite 数据库创建一个表。该表有 5 列，Int id、URL 链接、字符串标题、字符串描述和日期日期。
为了构建我的代码，我一直在使用this和this作为参考，但都没有展示如何向光标添加除字符串之外的任何内容。
这是我的代码：
public class Chapter {
final SimpleDateFormat FORMATTER =
new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z");
private String title;
private URL link;
private String description;
private Date date;
private int id;
//Constructor for table includes ID.
public Chapter(int id, URL link, String title, String description, Date date) {
this.id = id;
this.link = link;
this.title = title;
this.description = description;
this.date = date;
}
//Empty Constructor
public Chapter() {
// TODO Auto-generated constructor stub
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title.trim();
}
// getters and setters omitted for brevity
public URL getLink() {
return link;
}
public void setLink(String link) {
try {
this.link = new URL(link);
} catch (MalformedURLException e) {
throw new RuntimeException(e);
}
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description.trim();
}
public String getDate() {
return FORMATTER.format(this.date);
}
public void setDate(String date) {
// pad the date if necessary
while (!date.endsWith("00")){
date += "0";
}
date = "";
try {
this.date = FORMATTER.parse(date.trim());
} catch (ParseException e) {
throw new RuntimeException(e);
}
}
public Chapter copy(){
Chapter copy = new Chapter();
copy.title = title;
copy.link = link;
copy.description = description;
copy.date = date;
return copy;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("Title: ");
sb.append(title);
sb.append('\n');
sb.append("Date: ");
sb.append(this.getDate());
sb.append('\n');
sb.append("Link: ");
sb.append(link);
sb.append('\n');
sb.append("Description: ");
sb.append(description);
return sb.toString();
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((date == null) ? 0 : date.hashCode());
result = prime * result
+ ((description == null) ? 0 : description.hashCode());
result = prime * result + ((link == null) ? 0 : link.hashCode());
result = prime * result + ((title == null) ? 0 : title.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Chapter other = (Chapter) obj;
if (date == null) {
if (other.date != null)
return false;
} else if (!date.equals(other.date))
return false;
if (description == null) {
if (other.description != null)
return false;
} else if (!description.equals(other.description))
return false;
if (link == null) {
if (other.link != null)
return false;
} else if (!link.equals(other.link))
return false;
if (title == null) {
if (other.title != null)
return false;
} else if (!title.equals(other.title))
return false;
return true;
}
public int compareTo(Chapter another) {
if (another == null) return 1;
// sort descending, most recent first
return another.date.compareTo(date);
}
public int getId() {
// TODO Auto-generated method stub
return id;
}
public void setId(int parseInt) {
// TODO Auto-generated method stub
this.id = id;
}
public void setImage(String string) {
// TODO Auto-generated method stub
}
和我的助手类：
public class ChapterSQLiteOpenHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "chaptertable";
private static final int DATABASE_VERSION = 1;
// Database table
public static final String TABLE_CHAPTER = "Chapter";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_LINK = "link";
public static final String COLUMN_TITLE = "title";
public static final String COLUMN_DESCRIPTION = "description";
public static final String COLUMN_PUBDATE = "pubdate";
public static final String COLUMN_IMAGEID = "imageid";
// Database creation SQL statement
private static final String DATABASE_CREATE = "create table "
+ TABLE_CHAPTER
+ "("
+ COLUMN_ID + " integer primary key autoincrement, "
+ COLUMN_LINK + " text not null, "
+ COLUMN_TITLE + " text not null,"
+ COLUMN_DESCRIPTION + " text not null"
+ COLUMN_PUBDATE + " text not null,"
+ COLUMN_IMAGEID + " text not null,"
+ ");";
public ChapterSQLiteOpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Method is called during creation of the database
@Override
public void onCreate(SQLiteDatabase database) {
database.execSQL(DATABASE_CREATE);
}
// Method is called during an upgrade of the database,
// e.g. if you increase the database version
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_CHAPTER);
// Create tables again
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Adding new contact
void addContact(Chapter chapter) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(COLUMN_ID, chapter.getId()); // Chapter ID
values.put(COLUMN_LINK, chapter.getLink()); // Chapter Link
values.put(COLUMN_TITLE, chapter.getTitle()); // Chapter Title
values.put(COLUMN_DESCRIPTION, chapter.getDescription()); // Chapter Description
values.put(COLUMN_PUBDATE, chapter.getDate()); // Chapter Date
//values.put(COLUMN_IMAGEID, chapter.getImage()); // Chapter Image
// Inserting Row
db.insert(TABLE_CHAPTER, null, values);
db.close(); // Closing database connection
}
// Getting single contact
Chapter getChapter(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_CHAPTER, new String[] { COLUMN_ID,
COLUMN_ID, COLUMN_LINK }, COLUMN_ID + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Chapter chapter = new Chapter(Integer.parseInt(cursor.getString(0)), cursor.getURL(1), cursor.getString(2), cursor.getString(3), cursor.getString(4));
// return contact
return chapter;
}
// Getting All Contacts
public List<Chapter> getAllContacts() {
List<Chapter> chapterList = new ArrayList<Chapter>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_CHAPTER;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Chapter chapter = new Chapter();
chapter.setId(Integer.parseInt(cursor.getString(0)));
chapter.setLink(cursor.getURL(1));
chapter.setTitle(cursor.getString(2));
chapter.setDescription(cursor.getString(3));
chapter.setDate(cursor.getString(4));
//chapter.setImage(cursor.getString(5));
// Adding chapter to list
chapterList.add(chapter);
} while (cursor.moveToNext());
}
// return contact list
return chapterList;
}
// Updating single contact
public int updateContact(Chapter chapter) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(COLUMN_ID, chapter.getId());
values.put(COLUMN_LINK, chapter.getLink());
values.put(COLUMN_TITLE, chapter.getTitle());
values.put(COLUMN_DESCRIPTION, chapter.getDescription());
values.put(COLUMN_PUBDATE, chapter.getDate());
//values.put(COLUMN_IMAGEID, chapter.getImage());
// updating row
return db.update(TABLE_CHAPTER, values, COLUMN_ID + " = ?",
new String[] { String.valueOf(chapter.getId()) });
}
// Deleting single contact
public void deleteContact(Chapter chapter) {
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_CHAPTER, COLUMN_ID + " = ?",
new String[] { String.valueOf(chapter.getId()) });
db.close();
}
// Getting contacts Count
public int getChaptersCount() {
String countQuery = "SELECT * FROM " + TABLE_CHAPTER;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
cursor.close();
// return count
return cursor.getCount();
}
我在 values.put 行上得到编译错误链接，以及 Chapter chapter = new Chapter... 行。