java – Iterate through nested hashmap-ThrowExceptions

Exception or error: How would I go about iterating through a nested HashMap? The HashMap is setup like this: HashMap<String, HashMap<String, Student>> Where Student is an object containing a variable name. If for instance my HashMap looked like this (the following is not my code, it’s just to simulate what the contents of the hashmap …

java – "Illegal State Exception: Already Connected" when using HttpURLConnection-ThrowExceptions

Exception or error: I get an illegal state exception when i set DoOutput to true. public boolean sendLinksToMaster(String ipport, List<String> links){ boolean sent = false; String[] tokens = ipport.split(“:”); String data = edu.cis555.searchengine.utils.Utils.generateLinks(links); HttpURLConnection conn=null; try{ String encodedData = URLEncoder.encode(data, “UTF-8”); try{ String ip =tokens[0]; String port = tokens[1]; String path = edu.cis555.searchengine.utils.Constants.URL_ADD_LINK; System.setProperty(“http.keepAlive”, “false”); …

Provider org.glassfish.json.JsonProviderImpl not found at javax.json.spi.JsonProvider.provider(JsonProvider.java:97)-ThrowExceptions

Exception or error: How to run Java API for JSON Processing(JSR 374) in eclipse? I am trying to parse JSON string to JsonParser(javax.json.stream.JsonParser). Also added javax.json-api-1.0.jar in the build path. At runtime, there is an exception. My code is import java.io.StringReader; import javax.json.Json; import javax.json.JsonReader; import javax.json.JsonStructure; import javax.json.stream.JsonParser; import javax.json.stream.JsonParser.Event; import javax.json.JsonReader; import javax.json.JsonStructure; …

Collision Detection between two images in Java-ThrowExceptions

Exception or error: I have two characters displayed in a game I am writing, the player and the enemy. defined as such: public void player(Graphics g) { g.drawImage(plimg, x, y, this); } public void enemy(Graphics g) { g.drawImage(enemy, 200, 200, this); } Then called with: player(g); enemy(g); I am able to move player() around with …

Java Memory explained (SUN JVM)-ThrowExceptions

Exception or error: I tried to find an interpretation of the memory segments of the sun java vm, which would also be understandable by an administrator. It should explain what heap / non-heap memory is and the significance of the different memory pools. If it would somehow relate to the jconsole view, it would be …

java – Is Hibernate deprecated?-ThrowExceptions

Exception or error: This morning I was aboard a S-Bahn (German Subway) and I met a fellow student, who works for IBM. What he is doing there is Java EE optimization. I told him about my little project. And he recommended not to use ‘oldschool’ Hibernate. That’s why my question is: Is Hibernate deprecated? (In …