SessionFactory factory = null;
    Session session = null;
    try {
        factory = getSessionFactory();
        session = factory.openSession();

        final Criteria criteria = session
                .createCriteria(CrfEmailDataBean.class);
        criteria.add(Restrictions.eq(CAMPN_NBR,campNbr));
        returnList = criteria.list();
    } catch (Exception e) {
        logger.error(e.getMessage());
        throw new DAOException(e);
    } finally {
        DBUtil.close(factory,session);
    }
    if (logger.isInfoEnabled()) {
        logger.info(LOG_METHOD_EXIT);
    }
    return returnList;
}

在CrfEmailDataBean类中,我已经声明了一个私有的字符串crfEmailTypeCd;数据库中为null的字段.由于null,它不在返回列表中设置记录.如果我去数据库中的字段内输入一个值,它就会获取.

我尝试直接在sql数据库上运行查询,形成的查询是正确的并获取所有数据.

为什么不提取该记录？我该如何解决这个问题？

private int number;
private int value;
private char option;

如果hibernate数据库准备就绪,那么当Hibernate生成器的转换器出错时

>这种从不用户原始类型的解决方案
>或者为属性定义默认值
>每个其他可能性您的日期不为空,此值为白色
> white与null不同
>制作测试条件Restrictions.isNotNull.
>制作其他测试条件Restrictions.isNull.
>其他测试使一个方法接收int,调用send一个Integer null

第一项

private Integer number;
private Integer  value;
private Character option;

最后一项测试

public class Test{

    public static void setInt(int value){
       System.out.println(value);
    }

    public static void main(String[] args)
    {
        Integer testValue=null;
        Test.setInt(testValue);
    } }

import java.io.*;

public class NullFinalTest {
    public static void main(String[] args) throws IOException,ClassNotFoundException {
        Foo foo = new Foo();
        foo.useLock();
        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
        new ObjectOutputStream(buffer).writeObject(foo);
        foo = (Foo) new ObjectInputStream(new ByteArrayInputStream(buffer.toByteArray())).readobject();
        foo.useLock();
    }

    public static class Foo implements Serializable {
        private final String lockUsed = "lock used";
        private transient final Object lock = new Object();
        public void useLock() {
            System.out.println("About to synchronize");
            synchronized (lock) { // <- NullPointerException here on 2nd call
                System.out.println(lockUsed);
            }
        }
    }
}

这是输出：

About to synchronize
lock used
About to synchronize
Exception in thread "main" java.lang.NullPointerException
    at NullFinalTest$Foo.useLock(NullFinalTest.java:18)
    at NullFinalTest.main(NullFinalTest.java:10)

如何锁定可能为空？

以下是关于瞬态变量的一些事实：

– 在实例变量上使用Transient关键字时,将阻止该实例变量被序列化.

– 在反序列化时,瞬态变量达到其默认值…..

例如：

> Object Reference变量为null
> int到0
> boolean to false等等…….

这就是你在反序列化时获得NullPointerException的原因……

java.lang.IncompatibleClassChangeError: Couldn't find com.google.gson.annotations.Serializedname.value
at libcore.reflect.AnnotationAccess.toAnnotationInstance(AnnotationAccess.java:659)
at libcore.reflect.AnnotationAccess.toAnnotationInstance(AnnotationAccess.java:641)
at libcore.reflect.AnnotationAccess.getDeclaredAnnotation(AnnotationAccess.java:170)
at java.lang.reflect.Field.getAnnotation(Field.java:242)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getFieldName(ReflectiveTypeAdapterFactory.java:71)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getFieldName(ReflectiveTypeAdapterFactory.java:67)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:142)
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:83)
at com.google.gson.Gson.getAdapter(Gson.java:359)
at com.google.gson.Gson.fromJson(Gson.java:809)
at com.google.gson.Gson.fromJson(Gson.java:775)
at com.google.gson.Gson.fromJson(Gson.java:724)
at com.google.gson.Gson.fromJson(Gson.java:696)
at com.cubii.utils.SessionManager.getUserID(SessionManager.java:70)
at com.cubii.BluetoothLeService.broadcastUpdate(BluetoothLeService.java:188)
at com.cubii.BluetoothLeService.access$400(BluetoothLeService.java:47)
at com.cubii.BluetoothLeService$1.onCharacteristicChanged(BluetoothLeService.java:139)
at android.bluetooth.BluetoothGatt$1.onNotify(BluetoothGatt.java:443)
at android.bluetooth.IBluetoothGattCallback$Stub.onTransact(IBluetoothGattCallback.java:399)`enter code here`
at android.os.Binder.execTransact(Binder.java:446)

代码如下：

public int getUserID(){
    try {
        String json = preferences.getString("User","");

        LoginResponse loginResponse = new Gson().fromJson(json,LoginResponse.class);//getting error from this line

        Integer id = 0;
        if (loginResponse != null) {
            if (loginResponse.getId() != null) {
                id = loginResponse.getId();
            } else {
                id = loginResponse.getUserId();
            }
        }

        return (id == null) ? 0 : id;
    }catch (Exception e){
        Logger.dump(e);
    }
    return 0;
}

LoginResponse是我的POJO课程.

preferences.getString("User","")

将返回JSON字符串,这是服务器响应.

这里有更多关于此问题的报告,它只影响三星设备.
https://code.google.com/p/android/issues/detail?id=172339

编辑

他们中的一些人也在三星以外的设备上遇到这个问题,所以它可能不完全是三星的故障.此问题已分配给Google小组.作为Google团队成员之一,如果有人可以向团队分享错误报告,他们可以尽快解决此问题.

After reproducing the issue,navigate to developer settings,ensure
‘USB debugging’ is enabled,then enable ‘Bug report shortcut’. To take
bug report,hold the power button and select the ‘Take bug report’
option.

Note: Please upload the bug report to google drive and share the
folder to android-bugreport@google.com,then share the link 07002.

堆栈跟踪

java.lang.IncompatibleClassChangeError: interface not implemented
at in.plackal.lovecyclesfree.PasswordActivity.onCreate(PasswordActivity.java)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2627)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
at android.app.ActivityThread.access$2300(ActivityThread.java:125)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4627)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:878)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:636)
at dalvik.system.NativeStart.main(Native Method)

我的守则

public class PasswordActivity extends Activity implements Utilities
{
//Private Variables
private EditText m_passwrdEditText;

private TextView m_passwrdErrorText;

private Resources m_res;

@Override
public void onCreate(Bundle savedInstanceState) 
{
    //Setup the activity
    super.onCreate(savedInstanceState);
    this.requestwindowFeature(Window.FEATURE_NO_TITLE);
    setRequestedOrientation (ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);     
    displayMetrics dm = new displayMetrics();
    getwindowManager().getDefaultdisplay().getMetrics(dm);


    if(dm.widthPixels == 320 && dm.heightPixels == 480)
    {
        setContentView(R.layout.password_activity_hvga);
    }
    else
    {
        setContentView(R.layout.password_activity);
    }

    GoogleAnalyticsTracker tracker = GoogleAnalyticsTracker.getInstance();;
    tracker.startNewSession("UA-xxxxxxx-1",this);
    tracker.trackPageView("Password");
    tracker.dispatch();

    m_res = getResources();

    final Typeface face = Typeface.createFromAsset(getAssets(),"fonts/Cicle Semi.otf");     

    m_passwrdErrorText  = (TextView) findViewById(R.id.txt_error_message);
    m_passwrdErrorText.setTypeface(face);

    m_passwrdEditText  = (EditText) findViewById(R.id.txt_edit_passwrd);
    m_passwrdEditText.setonClickListener(new OnClickListener() 
    {           
        @Override
        public void onClick(View v) 
        {
            m_passwrdEditText.setHint("");
            m_passwrdEditText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
            m_passwrdEditText.setTypeface(face);
        }
    });

    m_passwrdEditText.setTypeface(face);

    m_passwrdEditText.setonKeyListener(new OnKeyListener() 
    {
        public boolean onKey(View v,int keyCode,KeyEvent event) 
        {           
            if ((event.getAction() == KeyEvent.ACTION_DOWN) && (keyCode == KeyEvent.KEYCODE_ENTER))
            {                             
                String strPassEntered = m_passwrdEditText.getText().toString();
                String strPassSaved = CycleManager.getSingletonObject().getpassWord();
                m_passwrdEditText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
                if (strPassSaved.equals(strPassEntered) || strPassEntered.equals(DEFAULT_PASSWORD))
                {
                    Intent intent = new Intent(PasswordActivity.this,ActivityManager.class);
                    startActivity(intent);  
                    PasswordActivity.this.finish();
                }
                else
                {
                    m_passwrdErrorText.setText(m_res.getString(R.string.passwrd_error_text));
                    m_passwrdEditText.setFocusable(true);                                           
                }
            }

            else if(keyCode == KeyEvent.KEYCODE_DEL)
            {
                m_passwrdEditText.setHint(m_res.getString(R.string.passwrd_hint_text));
                m_passwrdErrorText.setText("");
            }

            m_passwrdEditText.setTypeface(face);
            return false;
        }
  });
}
}

幸运的是,我室友的手机遇到了同样的异常.通过以下链接阅读：What causes java.lang.IncompatibleClassChangeError?,我修复它的方式(至少在我室友的手机上)是通过将android-support-v4.jar添加到项目的“libs”文件夹并添加到构建路径.然后在“订购和导出”下的项目“Java构建路径”部分中,导出新添加的jar文件并删除用于导出“Android私有库”的选择.

这是导致错误的代码行：(HomePageScreenTest.java:27)

@Rule
public ActivityTestRule<HomePageActivity> homePageActivityTestRule = new ActivityTestRule<>(HomePageActivity.class);

这是错误：

java.lang.IncompatibleClassChangeError: com.example.rocklee.mehmvp.HomePage.HomePageActivity
at dalvik.system.DexFile.defineClassNative(Native Method)
at dalvik.system.DexFile.defineClass(DexFile.java:226)
at dalvik.system.DexFile.loadClassBinaryName(DexFile.java:219)
at dalvik.system.DexPathList.findClass(DexPathList.java:321)
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:54)
at java.lang.classLoader.loadClass(ClassLoader.java:511)
at java.lang.classLoader.loadClass(ClassLoader.java:469)
at com.example.rocklee.mehmvp.HomePage.HomePageScreenTest.<init>(HomePageScreenTest.java:27)
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:288)
at org.junit.runners.BlockJUnit4ClassRunner.createTest(BlockJUnit4ClassRunner.java:217)
at org.junit.runners.BlockJUnit4ClassRunner$1.runReflectiveCall(BlockJUnit4ClassRunner.java:266)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runchild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runchild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runchildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runners.Suite.runchild(Suite.java:128)
at org.junit.runners.Suite.runchild(Suite.java:27)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runchildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:54)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:240)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853)

androidTestCompile 'com.android.support.test.espresso:espresso-contrib:2.2.1'

至

// Espresso-contrib for DatePicker,RecyclerView,Drawer actions,Accessibility checks,CountingIdlingResource
androidTestCompile ('com.android.support.test.espresso:espresso-contrib:2.2.1') {
    exclude module: 'support-annotations'
    exclude module: 'support-v4'
    exclude module: 'support-v13'
    exclude module: 'recyclerview-v7' 
}

我发现这个代码在jacobduron的评论this answer,它修复了我的问题.