В Java, a низ е обект който представлява последователността от знаци. За да използваме Strings, трябва да импортираме низ клас, дефиниран в java.lang пакет. The Низов масив е масив от струни с фиксирана дължина. В този раздел ще научим как да конвертирате String в String масив .

Забележка: Java низовете са неизменни обекти, т.е. стойността на низа не може да бъде променена, след като бъде създаден.

Преобразуване на String в String масив

Има четири начина за конвертиране на String в String масив в Java:

tkinter рамка

1. Използване на метода String.split().
2. Използване на метода Pattern.split().
3. Използване на String[ ] подход
4. Използване на метода toArray().

Използване на метода String.split().

The String.split() се използва за разделяне на низа на отделни обекти на низове въз основа на дадения разделител (празно пространство или други символи). Можем да съхраняваме тези обекти директно в низов масив.

Нека разгледаме следния пример, където използваме метода String.split() за преобразуване на низ в низов масив.

TestSplitMethod.java

 public class TestSplitMethod { public static void main(String[] args) { //declaring and initializing a string String str = &apos;Converting string to string array using split() method&apos;; //declaring an empty string array String[] strArray = null; //converting using String.split() method with whitespace as a delimiter strArray = str.split(&apos; &apos;); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java.webp" alt="How to convert String to String array in Java"> <p> <strong>Example 2:</strong> </p> <p>In the following example, we have converted the string to a string array based on the delimiter that is a <strong>,</strong> (comma).</p> <p> <strong>TestSplitMethod2.java</strong> </p> <pre> public class TestSplitMethod2 { public static void main(String[] args) { String commaSeparatedStr = &apos;Hello,have,a,nice,day&apos;; String[] strArray = null; //empty string array //converting using String.split() method with comma as a delimiter strArray = commaSeparatedStr.split(&apos;,&apos;); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-2.webp" alt="How to convert String to String array in Java"> <h3>Using Pattern.split() Method</h3> <p>The Pattern.split() method is used to split the string into an array of strings with the help of regular expression (pattern) as the delimiter.</p> <p>In order to use the method, we need to import the <strong>Pattern</strong> class in our Java code as:</p> <pre> import java.util.regex.Pattern; </pre> <p>Let&apos;s consider the following example where we split a string into an array by using the delimiter as whitespace.</p> <p> <strong>SplitMethodOfPatternClass.java</strong> </p> <pre> //importing Pattern class import java.util.regex.Pattern; public class SplitMethodOfPatternClass { public static void main(String[] args) { //declaring and initializing a string String str = &apos;Converting string to string array using Pattern.split()&apos;; //declaring an empty string array String[] strArray = null; //parsing white space as a parameter Pattern ptr = Pattern.compile(&apos; &apos;); //storing the string elements in array after splitting strArray = ptr.split(str); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-3.webp" alt="How to convert String to String array in Java"> <p> <strong>Example 2:</strong> </p> <p>We can also split a string into an array by using any string or pattern as a delimiter. Here, we have used the delimiter <strong>#a1.</strong> </p> <p> <strong>SplitMethodOfPatternClass2.java</strong> </p> <pre> //importing Pattern class import java.util.regex.Pattern; public class SplitMethodOfPatternClass2 { public static void main(String[] args) { //declaring and initializing a string with a separator String str = &apos;Hello #a1Ben #a1how #a1are #a1you ?&apos;; //declaring an empty string array String[] strArray = null; //splitting the string with delimiter as #a1 String patternStr = &apos;#a1&apos;; Pattern ptr = Pattern.compile(patternStr); //storing the string elements in array after splitting strArray = ptr.split(str); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-4.webp" alt="How to convert String to String array in Java"> <p>The above example splits the single string into five separate strings based on the delimiter #a1. The parts of the string that matched the delimiter are not included in the array.</p> <h3>Using String[ ] Approach</h3> <p>We can simply convert string to string array by using the string index [ ]. Here, we pass the string to <strong>String [ ] {}.</strong> </p> <p>Consider the following example where we have used the String[] to convert a string into a string array.</p> <p> <strong>StrToStrArray.java</strong> </p> <pre> import java.util.Arrays; public class StrToStrArray { public static void main(String[] args) { //declaring and initializing a string String str = &apos;Converting string to string array using String[]&apos;; //passing the string to String[] {} String[] strArray = new String[] {str}; //printing the string array using Arrays.toString() System.out.println(Arrays.toString(strArray)); } } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-5.webp" alt="How to convert String to String array in Java"> <h3>Using toArray() Method</h3> <p>We can also convert String to String array by using the <a href="/java-list-toarray-method">toArray()</a> method of the <a href="/java-list">List</a> class. It takes a list of type String as the input and converts each entity into a string array.</p> <p>Consider the following example where we have converted the list of strings into a string array.</p> <p> <strong>StringListtoArray.java</strong> </p> <pre> //importing ArrayList and List class import java.util.ArrayList; import java.util.List; public class StringListtoArray { public static void main(String[] args) { //creating a list of type string List list = new ArrayList (); //adding elements to list list.add(&apos;Hello&apos;); list.add(&apos;Welcome&apos;); list.add(&apos;To&apos;); list.add(&apos;Tutorial&apos;); //size of list int list_size = list.size(); //creating string array String[] strArray = new String[list_size]; //converting to string array list.toArray(strArray); //printing the string array for(int i = 0; i <strarray.length; i++) { system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-6.webp" alt="How to convert String to String array in Java"> <hr></strarray.length;></pre></strarray.length;></pre></strarray.length;></pre></strarray.length;></pre></strarray.length;>

Нека разгледаме следния пример, в който разделяме низ в масив, като използваме разделителя като интервал.

SplitMethodOfPatternClass.java

двоично дърво в java

 //importing Pattern class import java.util.regex.Pattern; public class SplitMethodOfPatternClass { public static void main(String[] args) { //declaring and initializing a string String str = &apos;Converting string to string array using Pattern.split()&apos;; //declaring an empty string array String[] strArray = null; //parsing white space as a parameter Pattern ptr = Pattern.compile(&apos; &apos;); //storing the string elements in array after splitting strArray = ptr.split(str); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-3.webp" alt="How to convert String to String array in Java"> <p> <strong>Example 2:</strong> </p> <p>We can also split a string into an array by using any string or pattern as a delimiter. Here, we have used the delimiter <strong>#a1.</strong> </p> <p> <strong>SplitMethodOfPatternClass2.java</strong> </p> <pre> //importing Pattern class import java.util.regex.Pattern; public class SplitMethodOfPatternClass2 { public static void main(String[] args) { //declaring and initializing a string with a separator String str = &apos;Hello #a1Ben #a1how #a1are #a1you ?&apos;; //declaring an empty string array String[] strArray = null; //splitting the string with delimiter as #a1 String patternStr = &apos;#a1&apos;; Pattern ptr = Pattern.compile(patternStr); //storing the string elements in array after splitting strArray = ptr.split(str); //printing the converted string array for (int i = 0; i<strarray.length; i++){ system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-4.webp" alt="How to convert String to String array in Java"> <p>The above example splits the single string into five separate strings based on the delimiter #a1. The parts of the string that matched the delimiter are not included in the array.</p> <h3>Using String[ ] Approach</h3> <p>We can simply convert string to string array by using the string index [ ]. Here, we pass the string to <strong>String [ ] {}.</strong> </p> <p>Consider the following example where we have used the String[] to convert a string into a string array.</p> <p> <strong>StrToStrArray.java</strong> </p> <pre> import java.util.Arrays; public class StrToStrArray { public static void main(String[] args) { //declaring and initializing a string String str = &apos;Converting string to string array using String[]&apos;; //passing the string to String[] {} String[] strArray = new String[] {str}; //printing the string array using Arrays.toString() System.out.println(Arrays.toString(strArray)); } } </pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-5.webp" alt="How to convert String to String array in Java"> <h3>Using toArray() Method</h3> <p>We can also convert String to String array by using the <a href="/java-list-toarray-method">toArray()</a> method of the <a href="/java-list">List</a> class. It takes a list of type String as the input and converts each entity into a string array.</p> <p>Consider the following example where we have converted the list of strings into a string array.</p> <p> <strong>StringListtoArray.java</strong> </p> <pre> //importing ArrayList and List class import java.util.ArrayList; import java.util.List; public class StringListtoArray { public static void main(String[] args) { //creating a list of type string List list = new ArrayList (); //adding elements to list list.add(&apos;Hello&apos;); list.add(&apos;Welcome&apos;); list.add(&apos;To&apos;); list.add(&apos;Tutorial&apos;); //size of list int list_size = list.size(); //creating string array String[] strArray = new String[list_size]; //converting to string array list.toArray(strArray); //printing the string array for(int i = 0; i <strarray.length; i++) { system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-6.webp" alt="How to convert String to String array in Java"> <hr></strarray.length;></pre></strarray.length;></pre></strarray.length;>

Изход:

Използване на метода toArray().

Можем също да конвертираме String в String масив, като използваме toArray() метод на списък клас. Той приема списък от тип String като вход и преобразува всеки обект в низов масив.

Помислете за следния пример, където сме преобразували списъка с низове в низов масив.

StringListtoArray.java

 //importing ArrayList and List class import java.util.ArrayList; import java.util.List; public class StringListtoArray { public static void main(String[] args) { //creating a list of type string List list = new ArrayList (); //adding elements to list list.add(&apos;Hello&apos;); list.add(&apos;Welcome&apos;); list.add(&apos;To&apos;); list.add(&apos;Tutorial&apos;); //size of list int list_size = list.size(); //creating string array String[] strArray = new String[list_size]; //converting to string array list.toArray(strArray); //printing the string array for(int i = 0; i <strarray.length; i++) { system.out.println(strarray[i]); } < pre> <p> <strong>Output:</strong> </p> <img src="//techcodeview.com/img/java-tutorial/38/how-convert-string-string-array-java-6.webp" alt="How to convert String to String array in Java"> <hr></strarray.length;>