Error

[15:37:41] [Server thread/INFO]: Starting minecraft server version 1.7.9
[15:37:41] [Server thread/INFO]: Loading properties
[15:37:41] [Server thread/INFO]: Default game type: SURVIVAL
[15:37:41] [Server thread/INFO]: Generating keypair
[15:37:41] [Server thread/INFO]: Starting Minecraft server on *:25565
[15:37:42] [Server thread/INFO]: This server is running CraftBukkit version git-Bukkit-1.7.2-R0.3-56-g3779cff-b3072jnks (MC: 1.7.9) (Implementing API version 1.7.9-R0.1-SNAPSHOT)
[15:37:42] [Server thread/INFO]: (plugin name written here) Loading (plugin name written here) v1.0
[15:37:42] [Server thread/INFO]: Preparing level "world"
[15:37:42] [Server thread/INFO]: Preparing start region for level 0 (Seed: -1646492879818318113)
[15:37:43] [Thread-7/INFO]: ----- Bukkit Auto Updater -----
[15:37:43] [Thread-7/INFO]: It appears that you're running a Development Build, when you've specified in bukkit.yml that you prefer to run Recommended Builds.
[15:37:43] [Thread-7/INFO]: If you would like to be kept informed about new Development Build releases, it is recommended that you change 'preferred-channel' in your bukkit.yml to 'dev'.
[15:37:43] [Thread-7/INFO]: With that set, you will be told whenever a new version is available for download, so that you can always keep up to date and secure with the latest fixes.
[15:37:43] [Thread-7/INFO]: If you would like to disable this warning, simply set 'suggest-channels' to false in bukkit.yml.
[15:37:43] [Thread-7/INFO]: ----- ------------------- -----
[15:37:43] [Server thread/INFO]: Preparing spawn area: 28%
[15:37:44] [Server thread/INFO]: Preparing start region for level 1 (Seed: -1646492879818318113)
[15:37:45] [Server thread/INFO]: Preparing start region for level 2 (Seed: -1646492879818318113)
[15:37:45] [Server thread/INFO]: (plugin name written here) Enabling (plugin name written here) v1.0
[15:37:47] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it
[15:37:47] [Server thread/INFO]: Done (5.113s)! For help, type "help" or "?"
[15:37:48] [pool-3-thread-1/INFO]: (plugin name written here) Checking to see if the server can be bumped....
[15:37:48] [pool-3-thread-1/INFO]: (plugin name written here) The server does require bumping.
[15:37:48] [pool-3-thread-1/INFO]:  Attempting to run command /bump...
[15:37:49] [pool-3-thread-1/WARN]: Exception in thread "pool-3-thread-1"
[15:37:49] [pool-3-thread-1/WARN]: org.apache.commons.lang.UnhandledException: Plugin (plugin name written here) v1.0 generated an exception while executing task 2
    at org.bukkit.craftbukkit.v1_7_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoSuchFieldError: INSTANCE
    at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<init>(DefaultHttpRequestWriterFactory.java:52)
    at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<init>(DefaultHttpRequestWriterFactory.java:56)
    at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<clinit>(DefaultHttpRequestWriterFactory.java:46)
    at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<init>(ManagedHttpClientConnectionFactory.java:69)
    at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<init>(ManagedHttpClientConnectionFactory.java:81)
    at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<clinit>(ManagedHttpClientConnectionFactory.java:56)
    at org.apache.http.impl.conn.PoolingHttpClientConnectionManager$InternalConnectionFactory.<init>(PoolingHttpClientConnectionManager.java:487)
    at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:147)
    at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:136)
    at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:112)
    at com.gargoylesoftware.htmlunit.HtmlUnitHttpClientBuilder.configureConnectionManager(HttpWebConnection.java:975)
    at com.gargoylesoftware.htmlunit.HttpWebConnection.getResponse(HttpWebConnection.java:162)
    at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseFromWebConnection(WebClient.java:1297)
    at com.gargoylesoftware.htmlunit.WebClient.loadWebResponse(WebClient.java:1214)
    at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:325)
    at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:394)
    at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:379)
    at com.github.(plugin name written here).bump((plugin name written here).java:120)
    at com.github.(plugin name written here).bumpWithConfigSettings((plugin name written here).java:100)
    at com.github.(plugin name written here).attemptBump((plugin name written here).java:87)
    at com.github.(plugin name written here).(plugin name written here)$1.run((plugin name written here).java:38)
    at org.bukkit.craftbukkit.v1_7_R3.scheduler.CraftTask.run(CraftTask.java:53)
    at org.bukkit.craftbukkit.v1_7_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
    ... 3 more

[15:49:56] [Thread-4/INFO]: Stopping server