将Throwable.getStackTrace()的结果转换为描述堆栈跟踪的字符串的最简单方法是什么？

使用Throwable.printStackTrace(PrintWriter pw)来发送堆栈跟踪到一个适当的写作者。

import java.io.StringWriter;
import java.io.PrintWriter;

// ...

StringWriter sw = new StringWriter();
PrintWriter pw = new PrintWriter(sw);
e.printStackTrace(pw);
String sStackTrace = sw.toString(); // stack trace as a string
System.out.println(sStackTrace);

可以使用以下方法将Exception 堆栈跟踪转换为String。此类在 Apache commons-lang 中可用，这是具有许多流行开源的最常见的依赖库

org.apache.commons.lang.exception.ExceptionUtils.getStackTrace(Throwable)

这应该是可行的。

StringWriter sw = new StringWriter();
e.printStackTrace(new PrintWriter(sw));
String exceptionAsString = sw.toString();

如果你是为Android开发的，一个更简单的方法是使用这个。

import android.util.Log;

String stackTrace = Log.getStackTraceString(exception); 

其格式与getStacktrace相同，例如。

09-24 16:09:07.042: I/System.out(4844): java.lang.NullPointerException
09-24 16:09:07.042: I/System.out(4844):   at com.temp.ttscancel.MainActivity.onCreate(MainActivity.java:43)
09-24 16:09:07.042: I/System.out(4844):   at android.app.Activity.performCreate(Activity.java:5248)
09-24 16:09:07.043: I/System.out(4844):   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)
09-24 16:09:07.043: I/System.out(4844):   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)
09-24 16:09:07.043: I/System.out(4844):   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)
09-24 16:09:07.043: I/System.out(4844):   at android.app.ActivityThread.access$800(ActivityThread.java:139)
09-24 16:09:07.043: I/System.out(4844):   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
09-24 16:09:07.043: I/System.out(4844):   at android.os.Handler.dispatchMessage(Handler.java:102)
09-24 16:09:07.043: I/System.out(4844):   at android.os.Looper.loop(Looper.java:136)
09-24 16:09:07.044: I/System.out(4844):   at android.app.ActivityThread.main(ActivityThread.java:5097)
09-24 16:09:07.044: I/System.out(4844):   at java.lang.reflect.Method.invokeNative(Native Method)
09-24 16:09:07.044: I/System.out(4844):   at java.lang.reflect.Method.invoke(Method.java:515)
09-24 16:09:07.044: I/System.out(4844):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
09-24 16:09:07.044: I/System.out(4844):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)

Guava's Throwables class

如果你有实际的Throwable实例，Google Guava提供了Throwables.getStackTraceAsString().

举例说明。

String s = Throwables.getStackTraceAsString ( myException ) ;

警告：不包括原因（这通常是有用的部分！）。

public String stackTraceToString(Throwable e) {
    StringBuilder sb = new StringBuilder();
    for (StackTraceElement element : e.getStackTrace()) {
        sb.append(element.toString());
        sb.append("\n");
    }
    return sb.toString();
}

对我来说，最干净、最简单的方法是。

import java.util.Arrays;
Arrays.toString(e.getStackTrace());

public static String getStackTrace(Throwable t) {
    StringWriter sw = new StringWriter();
    t.printStackTrace(new PrintWriter(sw));
    return sw.toString();
}

下面的代码允许你以String的格式获得整个stackTrace，而不需要使用像log4J甚至java.util.Logger这样的API：

catch (Exception e) {
    StackTraceElement[] stack = e.getStackTrace();
    String exception = "";
    for (StackTraceElement s : stack) {
        exception = exception + s.toString() + "\n\t\t";
    }
    System.out.println(exception);
    // then you can send the exception string to a external file.
}

将堆栈跟踪打印成PrintStream，然后将其转换为String：

// ...

catch (Exception e)
{
    ByteArrayOutputStream out = new ByteArrayOutputStream(); 
    e.printStackTrace(new PrintStream(out));
    String str = new String(out.toByteArray());

    System.out.println(str);
}

这里有一个可以直接复制粘贴到代码中的版本。

import java.io.StringWriter; 
import java.io.PrintWriter;

//Two lines of code to get the exception into a StringWriter
StringWriter sw = new StringWriter();
new Throwable().printStackTrace(new PrintWriter(sw));

//And to actually print it
logger.info("Current stack trace is:\n" + sw.toString());

或者，在一个抓取块中

} catch (Throwable t) {
    StringWriter sw = new StringWriter();
    t.printStackTrace(new PrintWriter(sw));
    logger.info("Current stack trace is:\n" + sw.toString());
}

Arrays.toString(thrown.getStackTrace())

最简单的方法是将结果转换为字符串，我在我的程序中使用这个来打印堆栈跟踪

LOGGER.log(Level.SEVERE, "Query Builder Issue Stack Trace : {0} ,Message : {1} objid {2}", new Object[]{Arrays.toString(e.getStackTrace()), e.getMessage(),objId});

Kotlin >= 1.4

在一个Throwable上使用内置的函数stackTraceToString()。

Kotlin < 1.4

扩展Throwable类将给你提供String属性error.stackTraceString：

val Throwable.stackTraceString: String
  get() {
    val sw = StringWriter()
    val pw = PrintWriter(sw)
    this.printStackTrace(pw)
    return sw.toString()
  }

如果您使用的是Java 8，请尝试这样做

Arrays.stream(e.getStackTrace())
                .map(s->s.toString())
                .collect(Collectors.joining("\n"));

你可以找到由Throwable.java提供的getStackTrace()函数的代码为:

public StackTraceElement[] getStackTrace() {
    return getOurStackTrace().clone();
}

而对于StackTraceElement，它提供了toString()，如下所示：

public String toString() {
    return getClassName() + "." + methodName +
        (isNativeMethod() ? "(Native Method)" :
         (fileName != null && lineNumber >= 0 ?
          "(" + fileName + ":" + lineNumber + ")" :
          (fileName != null ?  "("+fileName+")" : "(Unknown Source)")));
}

因此，只要用"\n"加入StackTraceElement即可。

将堆栈跟踪记录打印成字符串

import java.io.PrintWriter;
import java.io.StringWriter;

public class StackTraceUtils {
    public static String stackTraceToString(StackTraceElement[] stackTrace) {
        StringWriter sw = new StringWriter();
        printStackTrace(stackTrace, new PrintWriter(sw));
        return sw.toString();
    }
    public static void printStackTrace(StackTraceElement[] stackTrace, PrintWriter pw) {
        for(StackTraceElement stackTraceEl : stackTrace) {
            pw.println(stackTraceEl);
        }
    }
}

当你想在不创建Throwable实例的情况下打印当前线程的堆栈跟踪时，这很有用--但请注意，创建新的Throwable并从那里获得堆栈跟踪实际上比调用Thread.getStackTrace更快、更便宜。

private String getCurrentStackTraceString() {
    StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
    return Arrays.stream(stackTrace).map(StackTraceElement::toString)
            .collect(Collectors.joining("\n"));
}

代码来自Apache Commons Lang 3.4 (JavaDoc):

public static String getStackTrace(final Throwable throwable) {
    final StringWriter sw = new StringWriter();
    final PrintWriter pw = new PrintWriter(sw, true);
    throwable.printStackTrace(pw);
    return sw.getBuffer().toString();
}

与其他答案的不同之处在于，它在PrintWriter上使用了autoFlush。

第一组评论中的巧妙狙击非常有趣，但这真的取决于你想做什么。如果你还没有正确的库，那么3行代码（如D.Wroblewski的答案）就很完美了。 相反，如果你已经有了apache.commons库（大多数大型项目都会有），那么Amar的答案就更短了。 好吧，你可能需要10分钟来获取库并正确安装它（如果你知道自己在做什么，那么不到一分钟）。Jarek Przygódzki有一个有趣的警告--"如果你不需要嵌套异常"。

但是如果我确实需要完整的堆栈跟踪，嵌套和所有？在这种情况下，秘诀是使用 apache.common 的 getFullStackTrace（参见 http://commons.apache.org/proper/commons-lang/javadocs/api-2.6/org/apache/commons/ lang/exception/ExceptionUtils.html#getFullStackTrace%28java.lang.Throwable%29)

它拯救了我的培根。谢谢你，阿玛尔，谢谢你的提示!

如果没有java.io.*，可以这样做。

String trace = e.toString() + "\n";                     

for (StackTraceElement e1 : e.getStackTrace()) {
    trace += "\t at " + e1.toString() + "\n";
}   

然后trace 变量保存您的堆栈跟踪。输出也包含初始原因，输出与printStackTrace()相同

例如，printStackTrace()产生的结果是：

java.io.FileNotFoundException: / (Is a directory)
    at java.io.FileOutputStream.open0(Native Method)
    at java.io.FileOutputStream.open(FileOutputStream.java:270)
    at java.io.FileOutputStream.<init>(FileOutputStream.java:213)
    at java.io.FileOutputStream.<init>(FileOutputStream.java:101)
    at Test.main(Test.java:9)

trace 字符串持有，当打印到stdout时

java.io.FileNotFoundException: / (Is a directory)
     at java.io.FileOutputStream.open0(Native Method)
     at java.io.FileOutputStream.open(FileOutputStream.java:270)
     at java.io.FileOutputStream.<init>(FileOutputStream.java:213)
     at java.io.FileOutputStream.<init>(FileOutputStream.java:101)
     at Test.main(Test.java:9)

使用Java 8 流媒体API，您可以做这样的事情。

Stream
    .of(throwable.getStackTrace())
    .map(StackTraceElement::toString)
    .collect(Collectors.joining("\n"));

它将接收堆栈跟踪元素的数组，将它们转换为字符串，并连接成多行字符串。

对笪瞵岔语的回答，也将包括例外情况的原因。

private String extrapolateStackTrace(Exception ex) {
    Throwable e = ex;
    String trace = e.toString() + "\n";
    for (StackTraceElement e1 : e.getStackTrace()) {
        trace += "\t at " + e1.toString() + "\n";
    }
    while (e.getCause() != null) {
        e = e.getCause();
        trace += "Cause by: " + e.toString() + "\n";
        for (StackTraceElement e1 : e.getStackTrace()) {
            trace += "\t at " + e1.toString() + "\n";
        }
    }
    return trace;
}

Scala版本

def stackTraceToString(e: Exception): String = {
  import java.io.PrintWriter
  val sw = new StringWriter()
  e.printStackTrace(new PrintWriter(sw))
  sw.toString
}

如果您不想使用外部库，并且您没有开发for Android，您可以像这样创建一个'扩展'方法。

public static String getStackTraceString(Throwable e) {
    return getStackTraceString(e, "");
}

private static String getStackTraceString(Throwable e, String indent) {
    StringBuilder sb = new StringBuilder();
    sb.append(e.toString());
    sb.append("\n");

    StackTraceElement[] stack = e.getStackTrace();
    if (stack != null) {
        for (StackTraceElement stackTraceElement : stack) {
            sb.append(indent);
            sb.append("\tat ");
            sb.append(stackTraceElement.toString());
            sb.append("\n");
        }
    }

    Throwable[] suppressedExceptions = e.getSuppressed();
    // Print suppressed exceptions indented one level deeper.
    if (suppressedExceptions != null) {
        for (Throwable throwable : suppressedExceptions) {
            sb.append(indent);
            sb.append("\tSuppressed: ");
            sb.append(getStackTraceString(throwable, indent + "\t"));
        }
    }

    Throwable cause = e.getCause();
    if (cause != null) {
        sb.append(indent);
        sb.append("Caused by: ");
        sb.append(getStackTraceString(cause, indent));
    }

    return sb.toString();
}

解决方案是将数组的 stackTrace 转换为字符串数据类型。请看下面的例子。

import java.util.Arrays;

try{

}catch(Exception ex){
    String stack = Arrays.toString(ex.getStackTrace());
    System.out.println("stack "+ stack);
}

我的oneliner，将堆栈跟踪转换为所附的多行字符串。

Stream.of(e.getStackTrace()).map((a) -> a.toString()).collect(Collectors.joining("\n", "[", "]"))

很容易 "按原样 "传递给记录器。

少量的选择

1. StringWriter sw = new StringWriter(); e.printStackTrace(new PrintWriter(sw)); String exceptionAsString = sw.toString();

2. 使用Google Guava lib String stackTrace = Throwables.getStackTraceAsString ( myException ) ;

3. org.apache.commons.lang.exception.ExceptionUtils.getStackTrace(Throwable)

 import java.io.PrintWriter;
import java.io.StringWriter;

public class PrintStackTrace {

    public static void main(String[] args) {

        try {
            int division = 0 / 0;
        } catch (ArithmeticException e) {
            StringWriter sw = new StringWriter();
            e.printStackTrace(new PrintWriter(sw));
            String exceptionAsString = sw.toString();
            System.out.println(exceptionAsString);
        }
    }
}

当你运行该程序时，输出结果将是类似的东西。

java.lang.ArithmeticException: / by zero
at PrintStackTrace.main(PrintStackTrace.java:9)

我想知道为什么没有人提到ExceptionUtils.getStackFrames(exception)

对我来说，这是最方便的方式，可以将堆栈跟踪及其所有原因转储到最后。

String.join("\n", ExceptionUtils.getStackFrames(exception));

老问题了，但我只想补充一个特殊的情况，即你不想打印所有的堆栈，通过删除一些你实际上不感兴趣的部分，排除某些类或包。

使用SelectivePrintWriter 代替PrintWriter：

// This filters out this package and up.
String packageNameToFilter = "org.springframework";

StringWriter sw = new StringWriter();
PrintWriter pw = new SelectivePrintWriter(sw, packageNameToFilter);
e.printStackTrace(pw);
String sStackTrace = sw.toString(); 
System.out.println(sStackTrace);

SelectivePrintWriter 类由以下给出：

public class SelectivePrintWriter extends PrintWriter {
    private boolean on = true;
    private static final String AT = "\tat";
    private String internal;

    public SelectivePrintWriter(Writer out, String packageOrClassName) {
        super(out);
        internal = "\tat " + packageOrClassName;
    }

    public void println(Object obj) {
        if (obj instanceof String) {
            String txt = (String) obj;
            if (!txt.startsWith(AT)) on = true;
            else if (txt.startsWith(internal)) on = false;
            if (on) super.println(txt);
        } else {
            super.println(obj);
        }
    }
}

请注意，此类可以很容易地适应正则表达式、contains 或其他条件进行过滤。另请注意，这取决于Throwable 实现细节（不太可能改变，但仍然如此）。

警告。这可能有点偏离主题，但是哦，好吧...;)

我不知道最初的发帖者reason是什么原因想把堆栈跟踪变成字符串。当堆栈跟踪应该在SLF4J/Logback LOG中结束，但没有抛出或应该抛出异常时，我是这样做的：

public void remove(List<String> ids) {
    if(ids == null || ids.isEmpty()) {
        LOG.warn(
            "An empty list (or null) was passed to {}.remove(List). " +
            "Clearly, this call is unneccessary, the caller should " + 
            "avoid making it. A stacktrace follows.", 
            getClass().getName(),
            new Throwable ("Stacktrace")
        );

        return;
    }

    // actual work, remove stuff
}

我喜欢它，因为它不需要外部库（除了你的日志后端，当然，大部分时间都会在这里）。

我不久前写了一些这方面的方法，所以我想为什么不把我的两分钱扔在这里呢。

/** @param stackTraceElements The elements to convert
 * @return The resulting string */
public static final String stackTraceElementsToStr(StackTraceElement[] stackTraceElements) {
    return stackTraceElementsToStr(stackTraceElements, "\n");
}

/** @param stackTraceElements The elements to convert
 * @param lineSeparator The line separator to use
 * @return The resulting string */
public static final String stackTraceElementsToStr(StackTraceElement[] stackTraceElements, String lineSeparator) {
    return stackTraceElementsToStr(stackTraceElements, lineSeparator, "");
}

/** @param stackTraceElements The elements to convert
 * @param lineSeparator The line separator to use
 * @param padding The string to be used at the start of each line
 * @return The resulting string */
public static final String stackTraceElementsToStr(StackTraceElement[] stackTraceElements, String lineSeparator, String padding) {
    String str = "";
    if(stackTraceElements != null) {
        for(StackTraceElement stackTrace : stackTraceElements) {
            str += padding + (!stackTrace.toString().startsWith("Caused By") ? "\tat " : "") + stackTrace.toString() + lineSeparator;
        }
    }
    return str;
}

/** @param stackTraceElements The elements to convert
 * @return The resulting string */
public static final String stackTraceCausedByElementsOnlyToStr(StackTraceElement[] stackTraceElements) {
    return stackTraceCausedByElementsOnlyToStr(stackTraceElements, "\n");
}

/** @param stackTraceElements The elements to convert
 * @param lineSeparator The line separator to use
 * @return The resulting string */
public static final String stackTraceCausedByElementsOnlyToStr(StackTraceElement[] stackTraceElements, String lineSeparator) {
    return stackTraceCausedByElementsOnlyToStr(stackTraceElements, lineSeparator, "");
}

/** @param stackTraceElements The elements to convert
 * @param lineSeparator The line separator to use
 * @param padding The string to be used at the start of each line
 * @return The resulting string */
public static final String stackTraceCausedByElementsOnlyToStr(StackTraceElement[] stackTraceElements, String lineSeparator, String padding) {
    String str = "";
    if(stackTraceElements != null) {
        for(StackTraceElement stackTrace : stackTraceElements) {
            str += (!stackTrace.toString().startsWith("Caused By") ? "" : padding + stackTrace.toString() + lineSeparator);
        }
    }
    return str;
}

/** @param e The {@link Throwable} to convert
 * @return The resulting String */
public static final String throwableToStrNoStackTraces(Throwable e) {
    return throwableToStrNoStackTraces(e, "\n");
}

/** @param e The {@link Throwable} to convert
 * @param lineSeparator The line separator to use
 * @return The resulting String */
public static final String throwableToStrNoStackTraces(Throwable e, String lineSeparator) {
    return throwableToStrNoStackTraces(e, lineSeparator, "");
}

/** @param e The {@link Throwable} to convert
 * @param lineSeparator The line separator to use
 * @param padding The string to be used at the start of each line
 * @return The resulting String */
public static final String throwableToStrNoStackTraces(Throwable e, String lineSeparator, String padding) {
    if(e == null) {
        return "null";
    }
    String str = e.getClass().getName() + ": ";
    if((e.getMessage() != null) && !e.getMessage().isEmpty()) {
        str += e.getMessage() + lineSeparator;
    } else {
        str += lineSeparator;
    }
    str += padding + stackTraceCausedByElementsOnlyToStr(e.getStackTrace(), lineSeparator, padding);
    for(Throwable suppressed : e.getSuppressed()) {
        str += padding + throwableToStrNoStackTraces(suppressed, lineSeparator, padding + "\t");
    }
    Throwable cause = e.getCause();
    while(cause != null) {
        str += padding + "Caused by:" + lineSeparator + throwableToStrNoStackTraces(e.getCause(), lineSeparator, padding);
        cause = cause.getCause();
    }
    return str;
}

/** @param e The {@link Throwable} to convert
 * @return The resulting String */
public static final String throwableToStr(Throwable e) {
    return throwableToStr(e, "\n");
}

/** @param e The {@link Throwable} to convert
 * @param lineSeparator The line separator to use
 * @return The resulting String */
public static final String throwableToStr(Throwable e, String lineSeparator) {
    return throwableToStr(e, lineSeparator, "");
}

/** @param e The {@link Throwable} to convert
 * @param lineSeparator The line separator to use
 * @param padding The string to be used at the start of each line
 * @return The resulting String */
public static final String throwableToStr(Throwable e, String lineSeparator, String padding) {
    if(e == null) {
        return "null";
    }
    String str = padding + e.getClass().getName() + ": ";
    if((e.getMessage() != null) && !e.getMessage().isEmpty()) {
        str += e.getMessage() + lineSeparator;
    } else {
        str += lineSeparator;
    }
    str += padding + stackTraceElementsToStr(e.getStackTrace(), lineSeparator, padding);
    for(Throwable suppressed : e.getSuppressed()) {
        str += padding + "Suppressed: " + throwableToStr(suppressed, lineSeparator, padding + "\t");
    }
    Throwable cause = e.getCause();
    while(cause != null) {
        str += padding + "Caused by:" + lineSeparator + throwableToStr(e.getCause(), lineSeparator, padding);
        cause = cause.getCause();
    }
    return str;
}

举例说明。

try(InputStream in = new FileInputStream(file)) {
    ...
} catch(IOException e) {
    String exceptionToString = throwableToStr(e);
    someLoggingUtility.println(exceptionToString);
    ...
}

印刷品:

java.io.FileNotFoundException: C:\test.txt (The system cannot find the file specified)
    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(Unknown Source)
    at java.io.FileInputStream.<init>(Unknown Source)
    at com.gmail.br45entei.Example.main(Example.java:32)