blocks|key|1749250|text|从Angsuman+Chakraborty+(存档)：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1749251|/**+Get+the+current+line+number.
+*+@return+int+-+Current+line+number.
+*/
public+static+int+getLineNumber()+{
++++return+Thread.currentThread().getStackTrace()[2].getLineNumber();
}|code-block|syntax|javascript|1749252|entityMap|0|LINK|mutability|MUTABLE|url|https://web.archive.org/web/20100818065334/http://blog.taragana.com:80/index.php/archive/core-java-how-to-get-java-source-code-line-number-file-name-in-code/^0|1|K|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

From <a href="https://web.archive.org/web/20100818065334/http://blog.taragana.com:80/index.php/archive/core-java-how-to-get-java-source-code-line-number-file-name-in-code/" rel="noreferrer">Angsuman Chakraborty</a> (archived) :
<pre><code>/** Get the current line number.
 * @return int - Current line number.
 */
public static int getLineNumber() {
 return Thread.currentThread().getStackTrace()[2].getLineNumber();
}
</code></pre>

blocks|key|1749621|text|我们最终在Android工作中使用了这样的自定义类：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1749622|import+android.util.Log;++++
public+class+DebugLog+{
+public+final+static+boolean+DEBUG+=+true;++++
+public+static+void+log(String+message)+{
++if+(DEBUG)+{
++++String+fullClassName+=+Thread.currentThread().getStackTrace()[2].getClassName();
++++String+className+=+fullClassName.substring(fullClassName.lastIndexOf(".")+%2B+1);
++++String+methodName+=+Thread.currentThread().getStackTrace()[2].getMethodName();
++++int+lineNumber+=+Thread.currentThread().getStackTrace()[2].getLineNumber();

++++Log.d(className+%2B+"."+%2B+methodName+%2B+"():"+%2B+lineNumber,+message);
++}
+}
}|code-block|syntax|javascript|1749623|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

We ended up using a custom class like this for our Android work:

<pre><code>import android.util.Log; 
public class DebugLog {
 public final static boolean DEBUG = true; 
 public static void log(String message) {
 if (DEBUG) {
 String fullClassName = Thread.currentThread().getStackTrace()[2].getClassName();
 String className = fullClassName.substring(fullClassName.lastIndexOf(".") + 1);
 String methodName = Thread.currentThread().getStackTrace()[2].getMethodName();
 int lineNumber = Thread.currentThread().getStackTrace()[2].getLineNumber();

 Log.d(className + "." + methodName + "():" + lineNumber, message);
 }
 }
}
</code></pre>

blocks|key|1534735|text|快速和肮脏的方式：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1534736|System.out.println("I'm+in+line+#"+%2B+
++++new+Exception().getStackTrace()[0].getLineNumber());|code-block|syntax|javascript|1534737|有更多的细节：|1534738|StackTraceElement+l+=+new+Exception().getStackTrace()[0];
System.out.println(
++++l.getClassName()%2B"/"%2Bl.getMethodName()%2B":"%2Bl.getLineNumber());|1534739|这将输出如下所示：|1534740|com.example.mytest.MyClass/myMethod:103|1534741|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Quick and dirty way:

<pre><code>System.out.println("I'm in line #" + 
 new Exception().getStackTrace()[0].getLineNumber());
</code></pre>

With some more details:

<pre><code>StackTraceElement l = new Exception().getStackTrace()[0];
System.out.println(
 l.getClassName()+"/"+l.getMethodName()+":"+l.getLineNumber());
</code></pre>

That will output something like this:

<pre><code>com.example.mytest.MyClass/myMethod:103
</code></pre>

blocks|key|1749391|text|由@simon.buchan发布的代码将会工作...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1749392|Thread.currentThread().getStackTrace()[2].getLineNumber()|code-block|syntax|javascript|1749393|但是如果在方法中调用它，它总是返回方法中的行号，所以应该使用内联代码片段。|1749394|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

The code posted by @simon.buchan will work...

<pre><code>Thread.currentThread().getStackTrace()[2].getLineNumber()
</code></pre>

But if you call it in a method it will always return the line number of the line in the method so rather use the code snippet inline.

blocks|key|1749516|text|我建议使用诸如log4j之类的日志记录工具包。日志记录可以在运行时通过属性文件进行配置，您可以打开/关闭行号/文件名日志记录等特性。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1749517|查看PatternLayout的javadoc会给出完整的选项列表--您想要的是%25L。|1749518|entityMap|0|LINK|mutability|MUTABLE|url|http://logging.apache.org/log4j/|1|http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/PatternLayout.html^0|7|5|0|0|2|D|1|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@$A|Q|B|R|1|S]]|C|$]]|$1|D|3|E|5|6|7|T|8|@]|9|@$A|U|B|V|1|W]]|C|$]]|$1|F|3|-4|5|6|7|X|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]|N|$5|I|J|K|C|$L|O]]]]

I would recommend using a logging toolkit such as <a href="http://logging.apache.org/log4j/" rel="noreferrer">log4j</a>. Logging is configurable via properties files at runtime, and you can turn on / off features such as line number / filename logging.

Looking at the javadoc for the <a href="http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/PatternLayout.html" rel="noreferrer">PatternLayout</a> gives you the full list of options - what you're after is %L.

blocks|key|1749957|text|我使用这个小方法来输出调用它的方法的跟踪和行号。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1749958|+Log.d(TAG,+"Where+did+i+put+this+debug+code+again?+++"+%2B+Utils.lineOut());|code-block|syntax|javascript|1749959|双击输出转到该源代码行！|1749960|您可能需要根据放置代码的位置来调整level值。|1749961|public+static+String+lineOut()+{
++++int+level+=+3;
++++StackTraceElement[]+traces;
++++traces+=+Thread.currentThread().getStackTrace();
++++return+("+at+"++%2B+traces[level]+%2B+"+"+);
}|1749962|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|S|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I use this little method that outputs the trace and line number of the method that called it. 

<pre><code> Log.d(TAG, "Where did i put this debug code again? " + Utils.lineOut());
</code></pre>

Double click the output to go to that source code line!

You might need to adjust the level value depending on where you put your code.

<pre><code>public static String lineOut() {
 int level = 3;
 StackTraceElement[] traces;
 traces = Thread.currentThread().getStackTrace();
 return (" at " + traces[level] + " " );
}
</code></pre>

blocks|key|1534376|text|你不能保证代码行号的一致性，特别是如果它是为发布而编译的。为此，我不建议使用行号，最好给出异常发生位置的有效负载(简单的方法是将消息设置为包含方法调用的详细信息)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1534377|您可能希望将异常丰富看作是一种改进异常处理http://tutorials.jenkov.com/java-exception-handling/exception-enrichment.html的技术|offset|length|1534378|entityMap|0|LINK|mutability|MUTABLE|url|http://tutorials.jenkov.com/java-exception-handling/exception-enrichment.html^0|0|L|25|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

You can't guarantee line number consistency with code, especially if it is compiled for release. I would not recommend using line numbers for that purpose anyway, it would be better to give a payload of the place where the exception was raised (the trivial method being to set the message to include the details of the method call).

You might like to look at exception enrichment as a technique to improve exception handling 
<a href="http://tutorials.jenkov.com/java-exception-handling/exception-enrichment.html" rel="nofollow noreferrer">http://tutorials.jenkov.com/java-exception-handling/exception-enrichment.html</a>

blocks|key|1749452|text|如果它是为发布而编译的，这是不可能的。您可能希望查看诸如Log4J之类的内容，它会自动为您提供足够的信息，以便非常仔细地确定记录的代码发生在哪里。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1749453|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

If it's been compiled for release this isn't possible. You might want to look into something like Log4J which will automatically give you enough information to determine pretty closely where the logged code occurred.

blocks|key|1534631|text|首先是通用方法(在一个实用类中，不过在普通的旧java1.4代码中，您可能需要在java1.5或更高版本中重写它)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1534632|/**
+*+Returns+the+first+"[class#method(line)]:+"+of+the+first+class+not+equal+to+"StackTraceUtils"+and+aclass.+<br+/>
+*+Allows+to+get+past+a+certain+class.
+*+@param+aclass+class+to+get+pass+in+the+stack+trace.+If+null,+only+try+to+get+past+StackTraceUtils.+
+*+@return+"[class#method(line)]:+"+(never+empty,+because+if+aclass+is+not+found,+returns+first+class+past+StackTraceUtils)
+*/
public+static+String+getClassMethodLine(final+Class+aclass)++{
++++final+StackTraceElement+st+=+getCallingStackTraceElement(aclass);
++++final+String+amsg+=+"["+%2B+st.getClassName()+%2B+"#"+%2B+st.getMethodName()+%2B+"("+%2B+st.getLineNumber()
++++%2B")]+<"+%2B+Thread.currentThread().getName()+%2B+">:+";
++++return+amsg;
}|code-block|syntax|javascript|1534633|然后使用特定的实用方法来获取正确的stackElement：|1534634|/**
+++*+Returns+the+first+stack+trace+element+of+the+first+class+not+equal+to+"StackTraceUtils"+or+"LogUtils"+and+aClass.+<br+/>
+++*+Stored+in+array+of+the+callstack.+<br+/>
+++*+Allows+to+get+past+a+certain+class.
+++*+@param+aclass+class+to+get+pass+in+the+stack+trace.+If+null,+only+try+to+get+past+StackTraceUtils.+
+++*+@return+stackTraceElement+(never+null,+because+if+aClass+is+not+found,+returns+first+class+past+StackTraceUtils)
+++*+@throws+AssertionFailedException+if+resulting+statckTrace+is+null+(RuntimeException)
+++*/
++public+static+StackTraceElement+getCallingStackTraceElement(final+Class+aclass)+{
++++final+Throwable+++++++++++t+++++++++=+new+Throwable();
++++final+StackTraceElement[]+ste+++++++=+t.getStackTrace();
++++int+index+=+1;
++++final+int+limit+=+ste.length;
++++StackTraceElement+++st++++++++=+ste[index];
++++String++++++++++++++className+=+st.getClassName();
++++boolean+aclassfound+=+false;
++++if(aclass+==+null)+{
++++++++aclassfound+=+true;
++++}
++++StackTraceElement+++resst+=+null;
++++while(index+<+limit)+{
++++++++if(shouldExamine(className,+aclass)+==+true)+{
++++++++++++if(resst+==+null)+{
++++++++++++++++resst+=+st;
++++++++++++}
++++++++++++if(aclassfound+==+true)+{
++++++++++++++++final+StackTraceElement+ast+=+onClassfound(aclass,+className,+st);
++++++++++++++++if(ast+!=+null)+{
++++++++++++++++++++resst+=+ast;
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++else
++++++++++++{
++++++++++++++++if(aclass+!=+null+&&+aclass.getName().equals(className)+==+true)+{
++++++++++++++++++++aclassfound+=+true;
++++++++++++++++}
++++++++++++}
++++++++}
++++++++index+=+index+%2B+1;
++++++++st++++++++=+ste[index];
++++++++className+=+st.getClassName();
++++}
++++if(isNull(resst))++{
++++++++throw+new+AssertionFailedException(StackTraceUtils.getClassMethodLine()+%2B+"+null+argument:"+%2B+"stack+trace+should+null");+//$NON-NLS-1$
++++}
++++return+resst;
++}

++static+private+boolean+shouldExamine(String+className,+Class+aclass)+{
++++++final+boolean+res+=+StackTraceUtils.class.getName().equals(className)+==+false+&&+(className.endsWith(LOG_UTILS
++++++++)+==+false+%7C%7C+(aclass+!=null+&&+aclass.getName().endsWith(LOG_UTILS)));
++++++return+res;
++}

++static+private+StackTraceElement+onClassfound(Class+aclass,+String+className,+StackTraceElement+st)+{
++++++StackTraceElement+++resst+=+null;
++++++if(aclass+!=+null+&&+aclass.getName().equals(className)+==+false)
++++++{
++++++++++resst+=+st;
++++++}
++++++if(aclass+==+null)
++++++{
++++++++++resst+=+st;
++++++}
++++++return+resst;
++}|1534635|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

first the general method (in an utility class, in plain old java1.4 code though, you may have to rewrite it for java1.5 and more)

<pre><code>/**
 * Returns the first "[class#method(line)]: " of the first class not equal to "StackTraceUtils" and aclass. &lt;br /&gt;
 * Allows to get past a certain class.
 * @param aclass class to get pass in the stack trace. If null, only try to get past StackTraceUtils. 
 * @return "[class#method(line)]: " (never empty, because if aclass is not found, returns first class past StackTraceUtils)
 */
public static String getClassMethodLine(final Class aclass) {
 final StackTraceElement st = getCallingStackTraceElement(aclass);
 final String amsg = "[" + st.getClassName() + "#" + st.getMethodName() + "(" + st.getLineNumber()
 +")] &lt;" + Thread.currentThread().getName() + "&gt;: ";
 return amsg;
}
</code></pre>

Then the specific utility method to get the right stackElement:

<pre><code>/**
 * Returns the first stack trace element of the first class not equal to "StackTraceUtils" or "LogUtils" and aClass. &lt;br /&gt;
 * Stored in array of the callstack. &lt;br /&gt;
 * Allows to get past a certain class.
 * @param aclass class to get pass in the stack trace. If null, only try to get past StackTraceUtils. 
 * @return stackTraceElement (never null, because if aClass is not found, returns first class past StackTraceUtils)
 * @throws AssertionFailedException if resulting statckTrace is null (RuntimeException)
 */
 public static StackTraceElement getCallingStackTraceElement(final Class aclass) {
 final Throwable t = new Throwable();
 final StackTraceElement[] ste = t.getStackTrace();
 int index = 1;
 final int limit = ste.length;
 StackTraceElement st = ste[index];
 String className = st.getClassName();
 boolean aclassfound = false;
 if(aclass == null) {
 aclassfound = true;
 }
 StackTraceElement resst = null;
 while(index &lt; limit) {
 if(shouldExamine(className, aclass) == true) {
 if(resst == null) {
 resst = st;
 }
 if(aclassfound == true) {
 final StackTraceElement ast = onClassfound(aclass, className, st);
 if(ast != null) {
 resst = ast;
 break;
 }
 }
 else
 {
 if(aclass != null &amp;&amp; aclass.getName().equals(className) == true) {
 aclassfound = true;
 }
 }
 }
 index = index + 1;
 st = ste[index];
 className = st.getClassName();
 }
 if(isNull(resst)) {
 throw new AssertionFailedException(StackTraceUtils.getClassMethodLine() + " null argument:" + "stack trace should null"); //$NON-NLS-1$
 }
 return resst;
 }

 static private boolean shouldExamine(String className, Class aclass) {
 final boolean res = StackTraceUtils.class.getName().equals(className) == false &amp;&amp; (className.endsWith(LOG_UTILS
 ) == false || (aclass !=null &amp;&amp; aclass.getName().endsWith(LOG_UTILS)));
 return res;
 }

 static private StackTraceElement onClassfound(Class aclass, String className, StackTraceElement st) {
 StackTraceElement resst = null;
 if(aclass != null &amp;&amp; aclass.getName().equals(className) == false)
 {
 resst = st;
 }
 if(aclass == null)
 {
 resst = st;
 }
 return resst;
 }
</code></pre>

blocks|key|1534808|text|这是我们使用的记录器。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1534809|它围绕Android+Logger并显示类名、方法名和行号。|1534810|http://www.hautelooktech.com/2011/08/15/android-logging/|offset|length|1534811|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|1K|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Q|8|@]|9|@$F|R|G|S|1|T]]|A|$]]|$1|H|3|-4|5|6|7|U|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|E]]]]

Here is the logger that we use. 

it wraps around Android Logger and display class name, method name and line number.

<a href="http://www.hautelooktech.com/2011/08/15/android-logging/" rel="nofollow">http://www.hautelooktech.com/2011/08/15/android-logging/</a>

blocks|key|1534855|text|看看this+link吧。在该方法中，当您双击LogCat的行时，您可以跳转到代码行。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1534856|您还可以使用以下代码获取行号：|1534857|public+static+int+getLineNumber()
{
++++int+lineNumber+=+0;
++++StackTraceElement[]+stackTraceElement+=+Thread.currentThread()
++++++++++++.getStackTrace();
++++int+currentIndex+=+-1;
++++for+(int+i+=+0;+i+<+stackTraceElement.length;+i%2B%2B)+{
++++++++if+(stackTraceElement[i].getMethodName().compareTo("getLineNumber")+==+0)
++++++++{
++++++++++++currentIndex+=+i+%2B+1;
++++++++++++break;
++++++++}
++++}

++++lineNumber+=+stackTraceElement[currentIndex].getLineNumber();

++++return+lineNumber;
}|code-block|syntax|javascript|1534858|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/10599298/779408^0|2|9|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|C|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

Look at <a href="https://stackoverflow.com/a/10599298/779408">this link</a>. In that method you can jump to your line code, when you double click on LogCat's row.

Also you can use this code to get line number:

<pre><code>public static int getLineNumber()
{
 int lineNumber = 0;
 StackTraceElement[] stackTraceElement = Thread.currentThread()
 .getStackTrace();
 int currentIndex = -1;
 for (int i = 0; i &lt; stackTraceElement.length; i++) {
 if (stackTraceElement[i].getMethodName().compareTo("getLineNumber") == 0)
 {
 currentIndex = i + 1;
 break;
 }
 }

 lineNumber = stackTraceElement[currentIndex].getLineNumber();

 return lineNumber;
}
</code></pre>

blocks|key|1749789|text|private+static+final+int+CLIENT_CODE_STACK_INDEX;

static+{
++++//+Finds+out+the+index+of+"this+code"+in+the+returned+stack+Trace+-+funny+but+it+differs+in+JDK+1.5+and+1.6
++++int+i+=+0;
++++for+(StackTraceElement+ste+:+Thread.currentThread().getStackTrace())+{
++++++++i%2B%2B;
++++++++if+(ste.getClassName().equals(Trace.class.getName()))+{
++++++++++++break;
++++++++}
++++}
++++CLIENT_CODE_STACK_INDEX+=+i;
}

private+String+methodName()+{
++++StackTraceElement+ste=Thread.currentThread().getStackTrace()[CLIENT_CODE_STACK_INDEX%2B1];
++++return+ste.getMethodName()%2B":"%2Bste.getLineNumber();
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1749790|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>private static final int CLIENT_CODE_STACK_INDEX;

static {
 // Finds out the index of "this code" in the returned stack Trace - funny but it differs in JDK 1.5 and 1.6
 int i = 0;
 for (StackTraceElement ste : Thread.currentThread().getStackTrace()) {
 i++;
 if (ste.getClassName().equals(Trace.class.getName())) {
 break;
 }
 }
 CLIENT_CODE_STACK_INDEX = i;
}

private String methodName() {
 StackTraceElement ste=Thread.currentThread().getStackTrace()[CLIENT_CODE_STACK_INDEX+1];
 return ste.getMethodName()+":"+ste.getLineNumber();
}
</code></pre>

blocks|key|1534998|text|这些都可以得到当前线程和方法的行号，如果您在期望出现异常的地方使用try+catch，那么这些行号将非常有用。但是，如果您想捕获任何未处理的异常，那么您将使用默认的未捕获异常处理程序，并且当前线程将返回处理程序函数的行号，而不是抛出异常的类方法。不使用Thread.currentThread()，只需使用由异常处理程序传入的Throwable：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1534999|Thread.setDefaultUncaughtExceptionHandler(new+Thread.UncaughtExceptionHandler()+{
++++++++++++public+void+uncaughtException(Thread+t,+Throwable+e)+{++++++++++++++
++++++++++++++++if(fShowUncaughtMessage(e,t))+++++++++++++++
++++++++++++++++++++System.exit(1);
++++++++++++}
++++++++});|code-block|syntax|javascript|1535000|在上面的示例中，在您的处理函数(fShowUncaughtMessage)中使用e.getStackTrace()来获取攻击者。|1535001|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

These all get you the line numbers of your current thread and method which work great if you use a try catch where you are expecting an exception. But if you want to catch any unhandled exception then you are using the default uncaught exception handler and current thread will return the line number of the handler function, not the class method that threw the exception. Instead of using Thread.currentThread() simply use the Throwable passed in by the exception handler:

<pre><code>Thread.setDefaultUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
 public void uncaughtException(Thread t, Throwable e) { 
 if(fShowUncaughtMessage(e,t)) 
 System.exit(1);
 }
 });
</code></pre>

In the above use e.getStackTrace()[0] in your handler function (fShowUncaughtMessage) to get the offender.

blocks|key|1535121|text|stackLevel取决于您调用此方法的深度。您可以尝试从0到一个大数字，看看有什么不同。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1535122|如果stackLevel是合法的，您将得到类似于java.lang.Thread.getStackTrace(Thread.java:1536)的字符串|1535123|public+static+String+getCodeLocationInfo(int+stackLevel)+{
++++++++StackTraceElement[]+stackTraceElements+=+Thread.currentThread().getStackTrace();
++++++++if+(stackLevel+<+0+%7C%7C+stackLevel+>=+stackTraceElements.length)+{
++++++++++++return+"Stack+Level+Out+Of+StackTrace+Bounds";
++++++++}
++++++++StackTraceElement+stackTraceElement+=+stackTraceElements[stackLevel];
++++++++String+fullClassName+=+stackTraceElement.getClassName();
++++++++String+methodName+=+stackTraceElement.getMethodName();
++++++++String+fileName+=+stackTraceElement.getFileName();
++++++++int+lineNumber+=+stackTraceElement.getLineNumber();

++++++++return+String.format("%25s.%25s(%25s:%25s)",+fullClassName,+methodName,+fileName,+lineNumber);
}|code-block|syntax|javascript|1535124|entityMap^0|0|A|0|2|A|O|1C|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@$9|S|A|T|B|C]|$9|U|A|V|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|W|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|N|$]]

The <code>stackLevel</code> depends on depth you call this method. You can try from 0 to a large number to see what difference. 

If <code>stackLevel</code> is legal, you will get string like <code>java.lang.Thread.getStackTrace(Thread.java:1536)</code>

<pre><code>public static String getCodeLocationInfo(int stackLevel) {
 StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
 if (stackLevel &lt; 0 || stackLevel &gt;= stackTraceElements.length) {
 return "Stack Level Out Of StackTrace Bounds";
 }
 StackTraceElement stackTraceElement = stackTraceElements[stackLevel];
 String fullClassName = stackTraceElement.getClassName();
 String methodName = stackTraceElement.getMethodName();
 String fileName = stackTraceElement.getFileName();
 int lineNumber = stackTraceElement.getLineNumber();

 return String.format("%s.%s(%s:%s)", fullClassName, methodName, fileName, lineNumber);
}
</code></pre>

blocks|key|1749826|text|我的方式对我有效|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1749827|String+str+=+"select+os.name+from+os+where+os.idos="%2Bnameid;++try+{
++++++++PreparedStatement+stmt+=+conn.prepareStatement(str);
++++++++ResultSet+rs+=+stmt.executeQuery();
++++++++if+(rs.next())+{
++++++++++++a+=+rs.getString("os.n1ame");//<<<----Here+is+the+ERROR++++++++++
++++++++}
++++++++stmt.close();
++}+catch+(SQLException+e)+{
++++++++System.out.println("error+line+:+"+%2B+e.getStackTrace()[2].getLineNumber());++++++++++++
++++++++return+a;
++}|code-block|syntax|javascript|1749828|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

My way it works for me

<pre><code>String str = "select os.name from os where os.idos="+nameid; try {
 PreparedStatement stmt = conn.prepareStatement(str);
 ResultSet rs = stmt.executeQuery();
 if (rs.next()) {
 a = rs.getString("os.n1ame");//&lt;&lt;&lt;----Here is the ERROR 
 }
 stmt.close();
 } catch (SQLException e) {
 System.out.println("error line : " + e.getStackTrace()[2].getLineNumber()); 
 return a;
 }
</code></pre>

blocks|key|1535056|text|可以使用->+Reporter.log("")；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1535057|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

you can use -> Reporter.log("");

How to print line numbers to the log. Say when outputting some information to the log, I also want to print the line number where that output is in the source code. As we can see in the stack trace, it displays the line number where the exception has occurred. Stack trace is available on the exception object.

Other alternative could be like manually including the line number when printing to the log. Is there any other way?

How can we print line numbers to the log in java

Android

如何将行号打印到日志中。假设在将一些信息输出到日志时，我还想打印输出在源代码中的行号。正如我们在堆栈跟踪中看到的，它显示了发生异常的行号。堆栈跟踪在异常对象上可用。其他替代方法可以是在打印到日志时手动包含行号。还有别的办法吗？

问在java中如何将行号打印到日志中？
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