StackWalker walk(Function) in Java

walk(Function): This method is available in the java.lang.StackWalker class of Java.

Syntax:

<List<StackFrame>> List<StackFrame> java.lang.StackWalker.walk(Function<? super Stream<StackFrame>, ? extends List<StackFrame>> function)

This method takes one argument. This method applies the given function to the stream of StackFramesfor the current thread, traversing from the top frame of the stack,which is the method calling this walk method.

The StackFrame stream will be closed when this method returns. When a closed Stream<StackFrame> object is reused, IllegalStateException will be thrown.

Type Parameters: <T> The type of the result of applying the function to the stream of stack frame.

Parameters: One parameter is required for this method.

function: a function that takes a stream of stack frames and returns a result.

Returns: the result of applying the function to the stream of stack frame.

Exceptions: NA

Approach

Java

package com.StackWalker;

import java.lang.StackWalker.Option;
import java.lang.StackWalker.StackFrame;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

public class StackWalkerwalk {
    public static void main(String[] args) {

        Set<Option> options = new HashSet<>();
        options.add(Option.RETAIN_CLASS_REFERENCE);
        options.add(Option.SHOW_HIDDEN_FRAMES);
        StackWalker stackWalker = 
                      StackWalker.getInstance(options);

        List<StackFrame> stack = 
          stackWalker.walk(s -> 
                   s.limit(10).collect(Collectors.toList()));
        System.out.println(stack);
    }
}

Output:

[com.StackWalker.StackWalkerwalk.main(StackWalkerwalk.java:18)]

Some other methods of StackWalker

forEach(Consumer): This method performs the given action on each element of the StackFrame stream of the current thread, traversing from the top frame of the stack, which is the method calling this forEach method.

getCallerClass(): This method gets the Class object of the caller who invoked the method that invoked getCallerClass.

StackWalker.getInstance(): This method returns a StackWalker instance.

StackWalker.getInstance(Set): This method returns a StackWalker instance with the given options specifying the stack frame information it can access.

StackWalker.getInstance(Option): This method returns a StackWalker instance with the given option specifying the stack frame information it can access.

StackWalker.getInstance(Set, int): This method returns a StackWalker instance with the given options specifying the stack frame information it can access.

walk(Function): This method applies the given function to the stream of StackFramesfor the current thread, traversing from the top frame of the stack, which is the method calling this walk method.