新增自动关闭数据库连接功能，减少性能损耗

Author: li6185377

Demo-iOS/iOS-Demo/AppDelegate.m

@@ -177,10 +177,11 @@ -(void)test
 
 
     ///
-    addText(@"休息2秒 开始  为了说明 是异步插入的\n"
+    addText(@"休息25秒, 为了说明 是异步插入的\n, 测试自动关闭数据库连接的可用性"
             "rest for 2 seconds to start is asynchronous inserted to illustrate");
 
-    sleep(2);
+    /// 测试 自动关闭数据库连接
+    sleep(25);
 
     addText(@"休息2秒 结束 \n rest for 2 seconds at the end");
 

LKDBHelper.podspec.json

@@ -1,6 +1,6 @@
 {
   "name": "LKDBHelper",
-  "version": "2.4.3",
+  "version": "2.4.6",
   "summary": "全自动的插入,查询,更新,删除， an automatic database operation thread-safe and not afraid of recursive deadlock",
   "description": "全面支持 NSArray,NSDictionary, ModelClass, NSNumber, NSString, NSDate, NSData, UIColor, UIImage, CGRect, CGPoint, CGSize, NSRange, int,char,float, double, long.. 等属性的自动化操作(插入和查询)",
   "homepage": "https://github.com/li6185377/LKDBHelper-SQLite-ORM",
@@ -10,7 +10,7 @@
   },
   "source": {
     "git": "https://github.com/li6185377/LKDBHelper-SQLite-ORM.git",
-    "tag": "2.4.3"
+    "tag": "2.4.6"
   },
   "platforms": {
     "ios": "4.3",

LKDBHelper/Helper/LKDBHelper.h

@@ -47,6 +47,11 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (void)closeDB;
 
+/**
+ *    @brief  当数据库无操作 多少秒后 自动关闭数据库连接, 区间 [10 ~ int_max]  默认：20秒
+ */
+- (void)setAutoCloseDBTime:(NSInteger)time;
+
 /**
  *  @brief current encryption key.
  */

LKDBHelper/Helper/LKDBHelper.m

@@ -59,6 +59,11 @@ @interface LKDBHelper ()
 @property (nonatomic, copy) NSString *dbPath;
 @property (nonatomic, strong) NSMutableArray *createdTableNames;
 @property (nonatomic, strong) NSRecursiveLock *threadLock;
+
+@property (nonatomic, assign) NSInteger lastExecuteDBTime;
+@property (nonatomic, assign) BOOL runingAutoCloseTimer;
+@property (nonatomic, assign) NSInteger autoCloseDBDelayTime;
+
 @end
 
 @implementation LKDBHelper
@@ -162,6 +167,9 @@ - (instancetype)initWithDBPath:(NSString *)filePath
             if (self) {
                 self.threadLock = [[NSRecursiveLock alloc] init];
                 self.createdTableNames = [NSMutableArray array];
+                self.lastExecuteDBTime = [[NSDate date] timeIntervalSince1970];
+                self.autoCloseDBDelayTime = 20;
+                [self startAutoCloseTimer];
 
                 [self setDBPath:filePath];
                 [LKDBHelper dbHelperWithPath:nil save:self];
@@ -265,14 +273,13 @@ - (void)executeDB:(void (^)(FMDatabase *db))block
         return;
     }
     [self.threadLock lock];
-
+    
     if (self.usingdb != nil) {
         block(self.usingdb);
     } else {
         if (self.bindingQueue == nil) {
             self.bindingQueue = [[FMDatabaseQueue alloc] initWithPath:self.dbPath
                                                                 flags:LKDBOpenFlags];
-            [self.createdTableNames removeAllObjects];
             [self.bindingQueue inDatabase:^(FMDatabase *db) {
                 db.logsErrors = LKDBLogErrorEnable;
                 if (_encryptionKey.length > 0) {
@@ -286,10 +293,45 @@ - (void)executeDB:(void (^)(FMDatabase *db))block
             self.usingdb = nil;
         }];
     }
-
+    
+    self.lastExecuteDBTime = [[NSDate date] timeIntervalSince1970];
+    
+    if (!self.runingAutoCloseTimer) {
+        [self startAutoCloseTimer];
+    }
+    
     [self.threadLock unlock];
 }
 
+- (void)setAutoCloseDBTime:(NSInteger)time {
+    if (time < 10) {
+        time = 10;
+    }
+    self.autoCloseDBDelayTime = time;
+}
+
+- (void)startAutoCloseTimer {
+    self.runingAutoCloseTimer = YES;
+    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(self.autoCloseDBDelayTime * NSEC_PER_SEC)), dispatch_get_global_queue(0, 0), ^{
+        [self.threadLock lock];
+        self.runingAutoCloseTimer = NO;
+        BOOL hasClosed = [self autoCloseDBConnection];
+        if (!hasClosed) {
+            [self startAutoCloseTimer];
+        }
+        [self.threadLock unlock];
+    });
+}
+
+- (BOOL)autoCloseDBConnection {
+    NSInteger now = [[NSDate date] timeIntervalSince1970];
+    if (now - self.lastExecuteDBTime > 10) {
+        [self closeDB];
+        return YES;
+    }
+    return NO;
+}
+
 - (BOOL)executeSQL:(NSString *)sql arguments:(NSArray *)args
 {
     __block BOOL execute = NO;