java

[Solved] Java Lambda Consumer Compilation behavior

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The problem is that your two lambdas could be using the value of datamap before it has been initialized. At least, that is what the JLS definite assignment rules are saying. This is what will happen when the ConsumerTest object is created: The bare object is allocated. The superclass constructor is called (Object()) which does … Read more

[Solved] How to retrieve specific values from String

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As suggested in the comments, you may split on & then on = , like this example : String testString = “param1=value1&param2=value2&param3=value3&param4=value4&param5=value5”; String[] paramValues = testString.split(“\\&”); for (String paramValue : paramValues) { System.out.println(paramValue.split(“\\=”)[1]); } solved How to retrieve specific values from String

[Solved] Can someone tell me what’s wrong with this java code?

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The default Scanner delimiter is a space. So, one of your next() calls is consuming the last name as well as the score (“Potter,72” for example). Hence, the nextInt() call is failing. Also, you seem to be trying to read four values when you have only two (considering the Scanner is treating the last name … Read more

[Solved] Search Tokens in java [closed]

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String.split() would be the ideal choice – it takes a regular expressions — which can be used to define everything from the very simplest of patterns to the most complex ones . As per Java API Doc – StringTokenizer is a legacy class that is retained for compatibility reasons although its use is discouraged in … Read more

[Solved] Constructor with two arguments Java

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If you want to initialize an empty AccountType object, then you need to add a no argument default constructor. public AccountType() { } If you need to set class variables after the object is initialized then you will need to add the appropriate setter methods. public void setAccountType(String accountNameType){ this.accountNameType = accountNameType; } public void … Read more

[Solved] If I have an array of 5 elements lets say (1,2,3,4,5) how do create a new one with double each integer?

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if you want values in a new array, then int[] array ={1,2,3,4,5}; int arrayLength = array.size(); int[] array2 = new int[arrayLength]; for(int i=0; i<arrayLength; i++) { array2[i] = array[i]*2; } If you want values doubles in the same array, then int[] array ={1,2,3,4,5}; for(int i=0; i<array.size(); i++) { array[i]*=2; } 0 solved If I have … Read more

[Solved] try and catch error with joptionpane

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The warning (which can be ignored) is telling you that the variable e you’ve declared in your catch block is not used. I know with IntelliJ IDEA you can remove the warning by changing the name of e to ignored. I’m not sure if NetBeans has a similar feature. However, your try block is rather … Read more

[Solved] In java constructor and main which one will execute first?

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The main method will always be excecuted first, because it is a special static method that will be called from Java itself to start an application. For more about the main method please read Java main() Method Explained for example. Constructors will be created on object creation – in your case no object creation happens … Read more

[Solved] How to read file into an Arraylist and print the ArrayList in Java

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The Correct Syntax for Scanner : Scanner s = new Scanner(new File(“A.txt”) ); Object In java Object is the superclass of all the classes ie. predefined sucs as String or any user defined . It will accepts any kind of data such as string or any other types contained in the A.txt file. ======================================================================== import … Read more