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Showing reflection and other hidden frames

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A couple of other options allow stack traces to include implementation and/or reflection frames. This may be useful for debugging purposes. For instance, we can add the SHOW_REFLECT_FRAMES option to the StackWalker instance upon creation, so that the frames for the reflective methods are printed as well: 

package test;

import java.lang.StackWalker.Option;
import java.lang.StackWalker.StackFrame;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.List;
import java.util.stream.Collectors;

public class StackWalkerExample {

    public static void main(String[] args) throws NoSuchMethodException, SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
        Method fooMethod = FooHelper.class.getDeclaredMethod("foo", (Class<?>[])null);
        fooMethod.invoke(null, (Object[]) null);
    }
}

class FooHelper {
    protected static void foo() {
        BarHelper.bar();
    }
}

class BarHelper {
    protected static void bar() {
        // show reflection methods
        List<StackFrame> stack = StackWalker.getInstance(Option.SHOW_REFLECT_FRAMES)
                .walk((s) -> s.collect(Collectors.toList()));
        for(StackFrame frame : stack) {
            System.out.println(frame.getClassName() + " " + frame.getLineNumber() + " " + frame.getMethodName());
        }
    }
}

Output: 

test.BarHelper 27 bar
test.FooHelper 20 foo
jdk.internal.reflect.NativeMethodAccessorImpl -2 invoke0
jdk.internal.reflect.NativeMethodAccessorImpl 62 invoke
jdk.internal.reflect.DelegatingMethodAccessorImpl 43 invoke
java.lang.reflect.Method 563 invoke
test.StackWalkerExample 14 main

Note that line numbers for some reflection methods may not be available so StackFrame.getLineNumber() may return negative values.

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Stack-Walking API:
* Stack-Walking API
* Print all stack frames of the current thread
* Print current caller class
* Showing reflection and other hidden frames
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0 Inheritance
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125 Java command: java and javaw
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129 sun.misc.Unsafe
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148 Java Editions, versions, releases and distributions
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152 Generating Java Code
153 JShell
154 Benchmarks
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156 Multi-release JAR files
157 Stack-Walking API
158 TreeMap and TreeSet
159 Sockets
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161 Using other scripting languages in Java
162 Functional interfaces
163 List vs. set
164 2D graphics
165 Reflection
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180 StringBuffer
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182 C++ Comparison
183 CompletableFuture
184 Contributors