Concatenating arrays

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Problem Join an array of strings together to create a single string. Example: String[] strings = { "First ", "Second ", "Third" }; Would have output: "First Second Third"		More with Arrays
Solution There are multiple ways of joining strings together. The simplest way is to use the plus symbol, which you are probably familiar with. for( int i = 0; i < strings.length; i++ ) { tempString1 = tempString1 + strings[i]; } System.out.println( "1. " + tempString1 ); The String class also offers the method concat() to concatenate strings. for( int i = 0; i < strings.length; i++ ) { tempString2 = tempString2.concat( strings[i] ); } System.out.println( "2. " + tempString2 ); Java also offers the StringBuilder class which is best used when building up larger strings. for( int i = 0; i < strings.length; i++ ) { sb.append( strings[i] ); } tempString3 = sb.toString(); System.out.println( "3. " + tempString3 );
Code Solution Code public class stringTests { public static void main(String[] args) { String tempString1 = new String(); String tempString2 = new String(); String tempString3 = new String(); String[] strings = { "First ", "Second ", "Third" }; for( int i = 0; i < strings.length; i++ ) { tempString1 = tempString1 + strings[i]; } System.out.println( "1. " + tempString1 ); for( int i = 0; i < strings.length; i++ ) { tempString2 = tempString2.concat( strings[i] ); } System.out.println( "2. " + tempString2 ); StringBuilder sb = new StringBuilder(); for( int i = 0; i < strings.length; i++ ) { sb.append( strings[i] ); } tempString3 = sb.toString(); System.out.println( "3. " + tempString3 ); } }

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