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

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.
}

其他回答

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);

我不久前写了一些方法,所以我想为什么不花我的两分钱。

/** @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;
}

例子:

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

打印:

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)

解决方案是将数组的stackTrace转换为字符串数据类型。请参见以下示例:

import java.util.Arrays;

try{

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

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();
}

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)