java - How do I add a key listener to a LWJGL display? -

i trying add key listener display lwjgl. can see getting error in code, , think problem caused because trying trying add key listener, "input", class. in examples have seen key listener added jframe, not using 1 don't know add to. i'm providing class having error in , key listener created. please ignore of comments because majority of them failed pieces of code. error i'm getting on line 39 of initializer. line "this.addkeylistener(input);". thing wanted add, code between long lines of "/"s useless better ignore them. thank help.

import java.awt.cursor; import java.awt.point; import java.awt.toolkit; import java.awt.image.bufferedimage; import java.util.random; import org.lwjgl.lwjglexception; import org.lwjgl.input.keyboard;  import org.lwjgl.input.mouse; import org.lwjgl.opengl.display; import org.lwjgl.opengl.displaymode;  import static org.lwjgl.opengl.gl11.*;  public class initializer {     static int height = 800;     static int width = 600;     public static camera cam;     private inputhandler input;  public void start() {     try {         display.setdisplaymode(new displaymode(height,width));         display.settitle("3d opengl");         display.create();     } catch (lwjglexception e) {         e.printstacktrace();         system.exit(0);     }      // init opengl here     cam = new camera(70, (float)display.getwidth()/(float)display.getheight(), 0.3f, 1000);     float x = 0;      //makes cursor disappear     mouse.setgrabbed(true);     //displayexample.getcontentpane().setcursor(c);      input = new inputhandler();     this.addkeylistener(input);      keyboard.enablerepeatevents(false);      while (!display.iscloserequested() && !keyboard.iskeydown(keyboard.key_escape)) {          ///////////////////////////////////////////////         movement2vector movement = new movement2vector(0, 0);            //current issue 2 statements below not working check key pressed , if key pressed            int key = keyboard.geteventkey();         boolean pressed = keyboard.geteventkeystate();         system.out.println(pressed);         movement2vector vec = direction.of(key);         //system.out.println(vec.getx() + ", " + vec.gety());         if (pressed) {           movement = movement.add2vector(vec);           cam.movecam(movement);         } else if (movement != new movement2vector(0, 0) && movement == vec) {           movement = new movement2vector(0, 0);         }          ///////////////////////////////////////////////         //checks movement         //movement mov = new movement();         //initialized delta         delta.lastframe = delta.gettime();          // render opengl here         glclear(gl_color_buffer_bit | gl_depth_buffer_bit);         glloadidentity();         cam.useview();          glpushmatrix();         glcolor3f(1.0f, 0.5f, 0f);         gltranslatef(0,0,-10);         glrotatef(x, 2.5f, 1.5f , 0);         glcolor3f(0.0f, 1.0f, 1.0f);         createcube cube = new createcube(-1, 1, 1, 1, -1, -1);         /*glbegin(gl_quads);             //frontface             glvertex3f(-1,-1,1);             glvertex3f(-1,1,1);             glvertex3f(1,1,1);             glvertex3f(1,-1,1);              //backface             glvertex3f(-1,-1,-1);             glvertex3f(-1,1,-1);             glvertex3f(1,1,-1);             glvertex3f(1,-1,-1);              //bottomface             glvertex3f(-1,-1,-1);             glvertex3f(-1,-1,1);             glvertex3f(-1,1,1);             glvertex3f(-1,1,-1);              //topface             glvertex3f(1,-1,-1);             glvertex3f(1,-1,1);             glvertex3f(1,1,1);             glvertex3f(1,1,-1);              //leftface             glvertex3f(-1,-1,-1);             glvertex3f(1,-1,-1);             glvertex3f(1,-1,1);             glvertex3f(-1,-1,1);              //right face             glvertex3f(-1,1,-1);             glvertex3f(1,1,-1);             glvertex3f(1,1,1);             glvertex3f(-1,1,1);         glend();*/         glpopmatrix();         for(int i=-15; i<4; i++){             for(int y=-1; y<2; y++){                 random r = new random();                 glcolor3f(0.3f, 1.0f, 0.5f);                 createcube cubetest = new createcube(y-1, -4, i-1, y+1, -2, i+1);             }         }           x += 1f;         display.update();         display.sync(60);     }      display.destroy();     system.exit(1); }  public static void main(string[] args) {     initializer displayexample = new initializer();     displayexample.start(); } } 

key listener class

import java.awt.event.focusevent; import java.awt.event.focuslistener; import java.awt.event.keyevent; import java.awt.event.keylistener;  import org.lwjgl.input.keyboard;   public class inputhandler implements keylistener, focuslistener{      public boolean[] key = new boolean[68836];      @override     public void focusgained(focusevent e) {         // todo auto-generated method stub      }      @override     public void focuslost(focusevent e) {         // todo auto-generated method stub      }      @override     public void keypressed(keyevent e) {         if(keyboard.iskeydown(keyboard.key_w)){             initializer.cam.moveforward(0.005f*delta.getdelta());         }         else if(keyboard.iskeydown(keyboard.key_s)){             initializer.cam.moveforward(-0.005f*delta.getdelta());         }         else if(keyboard.iskeydown(keyboard.key_a)){             initializer.cam.movesideways(0.005f*delta.getdelta());         }         else if(keyboard.iskeydown(keyboard.key_d)){             initializer.cam.movesideways(-0.005f*delta.getdelta());         }         else if(keyboard.iskeydown(keyboard.key_space)){             initializer.cam.moveup(0.005f*delta.getdelta());         }         else if(keyboard.iskeydown(keyboard.key_lshift)){             initializer.cam.moveup(-0.005f*delta.getdelta());         }          /*int keycode = e.getkeycode();         if(keycode > 0 && keycode < key.length){             key[keycode] = true;         }*/      }      @override     public void keyreleased(keyevent e) {                /*for(int = 0; < key.length; i++){             key[i] = false;         }*/      }      @override     public void keytyped(keyevent e) {         // todo auto-generated method stub      }  } 

if using lwjgl can importimport org.lwjgl.input.keyboard; , can use instead find more efficient

if(keyboard.iskeydown(keyboard.key_left)){