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Re: hashCode help 15 Years Ago by BestJewSinceJC …Test is probably failing is because calling str.hashCode calls the hashCode method of the String class, it does …in your String. For example, [CODE] public static int hashCode(String str){ String str2 = str.substring(str.length() - … If you don't understand how to implement the hashCode method, then perhaps you should read about [URL="… Re: hashCode help 15 Years Ago by Alpdog14 …on the string [i]first[/i] and call hashcode on the returned substring. Edit: BTW "… test for this. I currently have: [CODE]@Test // hashCode() public void testHashCode1() { String str = "hello&…String str2 = "jello"; assertEquals(str.hashCode(), str2.hashCode()); }[/CODE] but the output is failing and giving… hashCode help 15 Years Ago by Alpdog14 …Here is my current code: [CODE]public int hashCode(String value){ String test = value; int hash…}[/CODE] Here is my Junit Test: [CODE] @Test // hashCode() public void testHashCode1() { //Integer key1 = 123; String key2 …quot;and"; assertEquals("and", key2.hashCode()); }[/CODE] Everytime I run my test it … Re: hashCode help 15 Years Ago by masijade Use substring on the string [i]first[/i] and call hashcode on the returned substring. Edit: BTW "as part of … tell us the [i]why[/i] you only want the hashcode of the last few chars (or the last few digits… of the hashcode, you don't seem to be too clear on [i… Re: hashCode help 15 Years Ago by jwenting trying to put business logic into your hashcode algorithm (which you're attempting to do) is almost …always a bad idea. The hashcode should be such that items can be quickly identified in…items returning true on calling equals() also returning the same hashcode, but that should be a natural consequence of the above… Re: hashCode help 15 Years Ago by Alpdog14 … though, here is my Revised code: [CODE]public static int hashCode(String str){ int zInt; //str = str.toString(); if(str.length… = "jello"; assertEquals("lo", key1.hashCode()); assertEquals("lo", key2.hashCode()); } }[/CODE] Trying to pull in the String… Re: hashCode help 15 Years Ago by Alpdog14 … entire thing?[/QUOTE] Well I am trying to return the hashCode of the last two or three digits because its part… take in parameters but how to I use the original hashCode() method that takes no parameters, here is my working code… Re: hashCode help 15 Years Ago by Alpdog14 [QUOTE=BestJewSinceJC;1138775]Well, can you post your current hashCode method so we can look at it and see why … be?[/QUOTE] Well my current code is: [CODE]public int hashCode(){ int hash = MyMap.key; String str = Integer.toString(MyMap.key… Re: hashCode help 15 Years Ago by BestJewSinceJC Your hashCode method returns an int. How could a String (which is … to tackle concepts such as hash tables (and by connection, hashCode). If you spend some serious time delving into some beginner… Re: hashCode help 15 Years Ago by masijade Well, certainly [i]not[/i] with * and + You're looking for substring if you [i]really[/i] want to do that, but I don't see any poinf to it, especially since hashcode is suppossed to return an int and not a String, so returning the "last 2 or 3 chars" isn't even applicable. Re: hashCode help 15 Years Ago by Alpdog14 … little but its still not returning, [CODE]@Override public int hashCode() { int hash = 1; Cell<K,V> cell = int… Re: hashCode help 15 Years Ago by masijade Like I said, use substring on the strings and call hashcode on that substring. Re: hashCode help 15 Years Ago by BestJewSinceJC Well, can you post your current hashCode method so we can look at it and see why that might be? Re: hashCode help 15 Years Ago by BestJewSinceJC [CODE] int number = 2567; String num = Integer.toString(number); String str = num.substring(//put correct argument here); [/CODE] I'm intentionally omitting the argument to substring so that I'm not just giving you all of the code. Oh, and keep in mind that in order to properly get the substring, you should check the length of the String first and… Re: hashCode help 15 Years Ago by masijade [i]Why[/i] do only want the last two digits? In any case, to return those as an int simply do modulus 100. Do you know what hascode is meant for? Even if you do only return the last two digits they will [i]still[/i] never match the original String. [i]What[/i], exactly, are you trying to acheive? What is your [i]goal[/i] with this entire thing… String Pool & hashCode wroking? 14 Years Ago by nitins60 …: "); System.out.println(s1.hashCode()+ " "+ s2.hashCode()+" "+s3.hashCode()); System.out.println("== Check: …understand why s1,s2,s3 are having same hashcode although i created as strings and objects as … working is fine. except that hashcode. if they are all having same hashcode how the == operator checks if … Re: String Pool & hashCode wroking? 14 Years Ago by ~s.o.s~ …can't understand why s1,s2,s3 are having same hashcode although i created as strings and objects as shown[/…quote] As already mentioned hashCode depends on the value of the object. Plus, when …equals() you need to provide a logical implementation of the hashCode() method which [URL="http://www.xyzws.com/javafaq/… equals & hashcode help 14 Years Ago by Alpdog14 … compares weight and value and I need help developing a hashcode and Junit tests to test them, here is my class…(t.weight)); } @Override public int hashCode(){ int h1 = new Double (value).hashCode(); int h2 = new Double (weight).hashCode(); final int HASH_MULTIPLIER = 29; int… Re: String Pool & hashCode wroking? 14 Years Ago by masijade Because the hashCode is based on the Strings [i]value[/i] not its reference. Re: String Pool & hashCode wroking? 14 Years Ago by masijade No, the "hash" has [i]nothing[/i] to do with the reference value. The "hash" is [i]calculated[/i] everytime you call the hashCode function and the calculation is based upon the Objects [i]value[/i] not its reference. Re: equals & hashcode help 14 Years Ago by ~s.o.s~ …) in which case you automatically get a good equals and hashCode implementation. Also, when you say 'weight', is it the physical… Eclipse, you can ask Eclipse to generate a equals() and hashCode() implementation for you. ALT + SHIFT + S then h… Re: equals & hashcode help 14 Years Ago by Alpdog14 …) in which case you automatically get a good equals and hashCode implementation. Also, when you say 'weight', is it the physical… Eclipse, you can ask Eclipse to generate a equals() and hashCode() implementation for you. ALT + SHIFT + S then h.[/QUOTE] This… Brute-forcing a String.hashCode() value 13 Years Ago by Delocaz …-force the result of something like [ICODE]"Hi".hashCode()[/ICODE]. I have no idea where to start. I looked…-force cracker on Google, and modify it to use [ICODE]hashCode()[/ICODE]. It went like [ICODE]"a", "b… Re: Brute-forcing a String.hashCode() value 13 Years Ago by JamesCherrill Sorry, but I'm not sufficiently sure that reverse-engineering a hashcode isn't for some dubious purpose, so I'm staying out of this. I suspect my colleagues feel the same. Maybe you can explain more about why you are doing this to reassure us that it's 100% legitimate? Re: Brute-forcing a String.hashCode() value 13 Years Ago by Delocaz It's to convert a Minecraft seed (hashCode() of string given by user, then used in a random generator as seed)(something like -6007422400597289330) to a textual representation (something like zQV5GH@zN). That makes it (somewhat) easier to remember. Re: Brute-forcing a String.hashCode() value 13 Years Ago by Delocaz Umm, the goal for this is like an MD5 brute-force cracker, but with String.hashCode(): Re: String Pool & hashCode wroking? 14 Years Ago by nitins60 then is there any way to print any values based on reference or creation of objects? Re: String Pool & hashCode wroking? 14 Years Ago by masijade What are you trying to accomplish? Edit: And no, you cannot print out the reference value (in the normal scheme of things), but trust me, the JVM has access to it. Re: String Pool & hashCode wroking? 14 Years Ago by nitins60 I believe its bit different in C#. in c#, whenever i create an object, that will return new hash value. but in Java, string pool is holding same hash for variable or object which reference to it. Re: equals & hashcode help 14 Years Ago by thekashyap [QUOTE=Alpdog14;1511940]Can anyone guide me on how to create the tests for this?[/QUOTE] In eclipse, right click on the .java file and say New->JUnit Testcase.. :) Select the methods you want to test, then implement the methods.