java - How to create a array of an object that requires parameters -


i have code here

final ship[] ships = new ship[3];  for(int x = 0; x < 3; x++) {     ships[x].settext("set ship length: " + (x+1)); // line in particular }

i getting null pointer exception, think because ships object requires string , int in parameters constructors contains, how supposed create , array of objects each object requires parameters?

change code below.. 

final ship[] ships = new ship[3];  for(int x = 0; x < 3; x++) {     ships[x].settext("set ship length: " + (x+1)); // line in particular }

to...

final ship[] ships = new ship[3];  for(int x = 0; x < 3; x++) {     string stringvalue = "set ship length: " + (x+1); //string want in ship object     int intvalue = 0; //int want in ship object..     ship ship = new ship(stringvalue, intvalue);     ships[x] = ship;     ships[x].settext("whatever string heart desires"); // line in particular }

you making array of type ship, but never assign contents array. therefore when try set text of element in array, trying set text on null value give null pointer exception.

instead need first create object of type ship have shown above , pass in string , integer parameters spoke of in question. add new object array. can access object in array , call methods on object.


Comments

Post a Comment

Popular posts from this blog

commonjs - How to write a typescript definition file for a node module that exports a function? -

consider, toml node module can use: // toml.d.ts declare module toml { export function parse(value:string):any; } declare module "toml" { export = toml; } then: /// <reference path="../../../../../defs/toml/toml.d.ts"/> import toml = require('toml'); toml.parse(...); however, node module export single function, such 'glob' ( https://github.com/isaacs/node-glob ). the node usage of module be: var glob = require("glob") glob("*.js", {}, callback(err, files) { ... }); you'd naively expect this: // glob.d.ts declare function globs(paths:string, options:any, callback:{(err:any, files:string[]):void; ...but because typescripts 'import' semantics bit strange, seems can use 'import .. = require()' statement alias modules . trying call: /// <reference path="../../../../../defs/glob/glob.d.ts"/> import blog = require('glob'); results in: error ts2072: mod...
Read more

openid - Okta: Failed to get authorization code through API call -

i'm integrating okta own idp server using okta's api. i'm implementing authorization code flow following steps below: in own server, use /api/v1/authn endpoint sessiontoken. use sessiontoken obtain authorization calling endpoint: /oauth2/v1/authorize?client_id=" + clientid + "&sessiontoken=" + sessiontoken + "&response_type=code&response_mode=query&scope=openid&redirect_uri=" + redirecturl + "&state=evanyang&nonce=" it's supposed return response status code 302 , location header containing redirect url code value. however, keep getting response status code 200 , without location header, html body saying "you using unsupported browser." , "javascript disabled on browser." according api documentation: http://developer.okta.com/docs/api/resources/oidc.html#authentication-request , sessiontoken parameter sufficient this: an okta one-time sessiontoken. allows api-based ...
Read more

ios - Change Storyboard View using Seague -

i have following code checks connection server, , depending on want change views if no connection found. nsstring *connect = [nsstring stringwithcontentsofurl:[nsurl urlwithstring:@"http://myserver.com"] encoding:nsutf8stringencoding error:nil]; if (connect == null) { [self performseguewithidentifier:@"network_failure" sender:self]; } else { // other code here } my problem not change views. have added storyboard segue between 2 views identifier of network_failure . not have navigation controller or that, problem? thanks help! no not problem. first of all, in objectivec exists nil object oriented null . must use that. so: if(connect == nil) or better: if(!connect) so due fact nil not same of null , probably code does't enter in if scope . you have been able discover breakpoint. anyway: be sure set trigger segue (line) 2 view controller , , name network_failure (that not best name. should instead view1toview2 ) as, m...
Read more