我正在创建一个简单的 android 应用程序，它使用httpRequest从 mysql 数据库中检索数据。
只需单击按钮，它将在日志中显示检索到的数据并使用意图显示第二页
但问题是应用程序工作并且它显示第二页但日志猫显示
日志猫
10-15 15:10:49.081: I/dalvikvm(1238): threadid=3: reacting to signal 3
10-15 15:10:49.210: I/dalvikvm(1238): Wrote stack traces to '/data/anr/traces.txt'
10-15 15:10:49.570: D/gralloc_goldfish(1238): Emulator without GPU emulation detected.
10-15 15:10:49.590: I/dalvikvm(1238): threadid=3: reacting to signal 3
10-15 15:10:49.600: I/dalvikvm(1238): Wrote stack traces to '/data/anr/traces.txt'
10-15 15:10:55.510: E/Error befor http(1238): Error before the http request
10-15 15:10:55.850: E/JSON PARSER Erro(1238): Error Prsing dataValue <!DOCTYPE of type java.lang.String cannot be converted to JSONObject
10-15 15:10:55.850: E/Error after http(1238): Error after the http request
10-15 15:10:55.850: D/AndroidRuntime(1238): Shutting down VM
10-15 15:10:55.850: W/dalvikvm(1238): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
10-15 15:10:55.880: E/AndroidRuntime(1238): FATAL EXCEPTION: main
10-15 15:10:55.880: E/AndroidRuntime(1238): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.lebdev.fitguide.activities/com.lebdev.fitguide.activities.SecondaryActivity}: java.lang.NullPointerException: println needs a message
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread.access$600(ActivityThread.java:123)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.os.Handler.dispatchMessage(Handler.java:99)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.os.Looper.loop(Looper.java:137)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread.main(ActivityThread.java:4424)
10-15 15:10:55.880: E/AndroidRuntime(1238): at java.lang.reflect.Method.invokeNative(Native Method)
10-15 15:10:55.880: E/AndroidRuntime(1238): at java.lang.reflect.Method.invoke(Method.java:511)
10-15 15:10:55.880: E/AndroidRuntime(1238): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
10-15 15:10:55.880: E/AndroidRuntime(1238): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
10-15 15:10:55.880: E/AndroidRuntime(1238): at dalvik.system.NativeStart.main(Native Method)
10-15 15:10:55.880: E/AndroidRuntime(1238): Caused by: java.lang.NullPointerException: println needs a message
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.util.Log.println_native(Native Method)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.util.Log.e(Log.java:231)
10-15 15:10:55.880: E/AndroidRuntime(1238): at com.lebdev.fitguide.om.JsonObjectMapper.jsonToStudent(JsonObjectMapper.java:27)
10-15 15:10:55.880: E/AndroidRuntime(1238): at com.lebdev.fitguide.activities.SecondaryActivity.onCreate(SecondaryActivity.java:47)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.Activity.performCreate(Activity.java:4465)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
10-15 15:10:55.880: E/AndroidRuntime(1238): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
10-15 15:10:55.880: E/AndroidRuntime(1238): ... 11 more
10-15 15:10:55.900: I/dalvikvm(1238): threadid=3: reacting to signal 3
10-15 15:10:55.980: I/dalvikvm(1238): Wrote stack traces to '/data/anr/traces.txt'
10-15 15:10:56.410: I/dalvikvm(1238): threadid=3: reacting to signal 3
10-15 15:10:56.410: I/dalvikvm(1238): Wrote stack traces to '/data/anr/traces.txt'
10-15 15:10:56.561: I/dalvikvm(1238): threadid=3: reacting to signal 3
10-15 15:10:56.571: I/dalvikvm(1238): Wrote stack traces to '/data/anr/traces.txt'
谁能帮我 ？？？？