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


当前回答

老问题,但我想补充一个特殊情况,即您不想打印所有堆栈,通过删除一些您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);

其中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,这个类可能很容易被Regex、contains或其他条件过滤掉。还要注意,这取决于可丢弃的实现细节(不太可能改变,但仍然如此)。

其他回答

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); 

格式与getStacktrace相同,例如。

09-24 16:09:07.042:I/System.out(4844):java.lang.NullPointerException09-24 16:09:07.042:I/System.out(4844):在com.temp.ttscancel.MainActivity.onCreate(MainActivity.java:43)09-24 16:09:07.042:I/System.out(4844):在android.app.Activity.performCreate(Activity.java:5248)09-24 16:09:07.043:I/System.out(4844):在android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)09-24 16:09:07.043:I/System.out(4844):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2162)09-24 16:09:07.043:I/System.out(4844):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2257)09-24 16:09:07.043:I/System.out(4844):在android.app.ActivityThread.access$800(ActivityThread.java:139)09-24 16:09:07.043:I/System.out(4844):在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)09-24 16:09:07.043:I/System.out(4844):在android.os.Handler.dispatchMessage(Handler.java:102)09-24 16:09:07.043:I/System.out(4844):在android.os.Looper.lop(Looper.java:136)09-24 16:09:07.044:I/System.out(4844):在android.app.ActivityThread.main(ActivityThread.java:5097)09-24 16:09:07.044:I/System.out(4844):在java.lang.reflect.Method.invokeNative(本机方法)09-24 16:09:07.044:I/System.out(4844):在java.lang.reflect.Method.invoke(Method.java:515)09-24 16:09:07.044:I/System.out(4844):在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)09-24 16:09:07.044:I/System.out(4844):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)

警告:这可能有点离题,但哦,好吧…;)

我不知道最初的海报是什么原因让堆栈跟踪成为字符串。当堆栈跟踪应该以SLF4J/Logback LOG结尾,但没有或应该抛出异常时,我会这样做:

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(当然,除了您的日志后端,它大部分时间都会在那里)。

如果你不想使用外部库,而且你不是为Android开发的,你可以创建这样的“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();
}

使用Throwable.printStackTrace(PrintWriter pw)将堆栈跟踪发送到适当的编写器。

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);

以下代码允许您使用字符串格式获取整个stackTrace,而无需使用log4J或java.util.Logger等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.
}