HTML to PDF

- itext 5.4.2 converting HTML to PDF + itext 7.1.9 + converting HTML to PDF

UTF-8 + RELEASE

- com.itextpdf - itextpdf - 5.4.2 - - - com.itextpdf.tool - xmlworker - 5.4.1 + com.itextpdf + itext7-core + 7.1.9 + pom + + + com.itextpdf + html2pdf + 2.1.6

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This was created using iText

hmkcode.com

e = Arrays.asList("A", "B", "C", "D", "E"); + int k = 3; + combination(e, k, ""); + + } + static int counter = 0; + public static void combination(List e, int k, String accumulated){ + + // 1. stop + if(e.size() < k) + return; + + // 2. add each element in e to accumulated + if(k == 1) + for(String s:e) + print(accumulated+s); + + // 3. add all elements in e to accumulated + else if(e.size() == k){ + for(String s:e) + accumulated+=s; + print(accumulated); + } + + // 4. for each element, call combination + else if(e.size() > k) + for(int i = 0 ; i < e.size() ; i++) + combination(e.subList(i+1, e.size()), k-1, accumulated+e.get(i)); + + } + + public static void print(String c){ + counter++; + System.out.println(counter+"\t"+c); + } +} diff --git a/java-combinations/src/main/java/com/hmkcode/Shifting.java b/java-combinations/src/main/java/com/hmkcode/Shifting.java new file mode 100644 index 00000000..d81ce2b5 --- /dev/null +++ b/java-combinations/src/main/java/com/hmkcode/Shifting.java @@ -0,0 +1,66 @@ +package com.hmkcode; + +public class Shifting +{ + public static void main( String[] args ) + { + String[] e = {"A","B","C","D","E"}; + int k = 3; + combination(e,k); + } + public static void combination(Object[] e, int k){ + + int[] ignore = new int[e.length-k]; // --> [0][0] + int[] combination = new int[k]; // --> [][][] + + // set initial ignored elements + //(last k elements will be ignored) + for(int w = 0; w < ignore.length; w++) + ignore[w] = e.length - k +(w+1); + + int i = 0, r = 0, g = 0; + + boolean terminate = false; + while(!terminate){ + + // selecting N-k non-ignored elements + while(i < e.length && r < k){ + + if(i != ignore[g]){ + combination[r] = i; + r++; i++; + } + else{ + if(g != ignore.length-1) + g++; + i++; + } + } + print(combination, e); + i = 0; r = 0; g = 0; + + terminate = true; + + // shifting ignored indices + for(int w = 0 ; w < ignore.length; w++){ + if(ignore[w] > w){ + ignore[w]--; + + if(w > 0) + ignore[w-1] = ignore[w]-1; + terminate = false; + break; + } + } + } + } + + private static void print(int[] combination, Object[] elements){ + + String output = ""; + for(int z = 0 ; z < combination.length;z++){ + output += elements[combination[z]]; + } + System.out.println(output); + } +} \ No newline at end of file diff --git a/java-jasper/pom.xml b/java-jasper/pom.xml new file mode 100644 index 00000000..37666f32 --- /dev/null +++ b/java-jasper/pom.xml @@ -0,0 +1,36 @@ + + + + 4.0.0 + + com.hmkcode + java-jasper + 1.0-SNAPSHOT + + java-jasper + + http://www.example.com + + + UTF-8 + 1.7 + 1.7 + + + + + net.sf.jasperreports + jasperreports + 6.10.0 + + + + + org.springframework + spring-core + 5.2.3.RELEASE + + + + diff --git a/java-jasper/src/main/java/com/hmkcode/App.java b/java-jasper/src/main/java/com/hmkcode/App.java new file mode 100644 index 00000000..72853237 --- /dev/null +++ b/java-jasper/src/main/java/com/hmkcode/App.java @@ -0,0 +1,61 @@ +package com.hmkcode; + +import net.sf.jasperreports.engine.*; +import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource; +import org.springframework.util.ResourceUtils; + +import java.io.*; +import java.util.*; + +public class App +{ + // name and destination of output file e.g. "report.pdf" + private static String destFileName = "report.pdf"; + public static void main( String[] args ) throws FileNotFoundException, JRException { + + System.out.println( "generating jasper report..." ); + + // 1. compile template ".jrxml" file + JasperReport jasperReport = getJasperReport(); + + // 2. parameters "empty" + Map parameters = getParameters(); + + // 3. datasource "java object" + JRDataSource dataSource = getDataSource(); + + JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, parameters, dataSource); + JasperExportManager.exportReportToPdfFile(jasperPrint, destFileName); + + } + + private static JasperReport getJasperReport() throws FileNotFoundException, JRException { + File template = ResourceUtils.getFile("classpath:report.jrxml"); + return JasperCompileManager.compileReport(template.getAbsolutePath()); + } + private static Map getParameters(){ + Map parameters = new HashMap<>(); + parameters.put("createdBy", "hmkcode"); + return parameters; + } + + private static JRDataSource getDataSource(){ + + List countries = new LinkedList<>(); + + countries.add(new Country("IS", "Iceland", "https://i.pinimg.com/originals/72/b4/49/72b44927f220151547493e528a332173.png")); + countries.add(new Country("TR", "Turkey", "https://i.pinimg.com/originals/82/63/23/826323bba32e6e5a5996062c3a3c662f.png")); + countries.add(new Country("ZA", "South Africa", "https://i.pinimg.com/originals/f5/c7/8d/f5c78da001b46e26481c04fb93473454.png")); + countries.add(new Country("PL", "Poland", "https://i.pinimg.com/originals/7f/ae/21/7fae21c4854010b11127218ead743863.png")); + countries.add(new Country("CA", "Canada", "https://i.pinimg.com/originals/4d/d4/01/4dd401733ba25e6442fc8696e04e5846.png")); + + countries.add(new Country("PA", "Panama", "https://i.pinimg.com/originals/84/dc/e4/84dce49e52ebfb5b3814393069807e0a.png")); + countries.add(new Country("HR", "Croatia", "https://i.pinimg.com/originals/f5/8c/94/f58c94a2a2b3221328fc1e2b7acfa656.png")); + countries.add(new Country("JP", "Japan", "https://i.pinimg.com/originals/a5/d6/88/a5d688289cd6850016f14fe93b17da01.png")); + countries.add(new Country("DE", "Germany", "https://i.pinimg.com/originals/af/c9/b2/afc9b2592a9f1cf591e8a52256ae1e9f.png")); + countries.add(new Country("BR", "Brazil", "https://i.pinimg.com/originals/e4/03/c4/e403c4447a3bd8940459ae4f50856bed.png")); + + + return new JRBeanCollectionDataSource(countries); + } +} diff --git a/java-jasper/src/main/java/com/hmkcode/Country.java b/java-jasper/src/main/java/com/hmkcode/Country.java new file mode 100644 index 00000000..ecbc501d --- /dev/null +++ b/java-jasper/src/main/java/com/hmkcode/Country.java @@ -0,0 +1,47 @@ +package com.hmkcode; + +public class Country { + + private String code; + private String name; + private String url; + + public Country(String code, String name, String url) { + this.code = code; + this.name = name; + this.url = url; + } + + public String getCode() { + return code; + } + + public void setCode(String code) { + this.code = code; + } + + public String getName() { + return name; + } + + public void setName(String name) { + this.name = name; + } + + public String getUrl() { + return url; + } + + public void setUrl(String url) { + this.url = url; + } + + @Override + public String toString() { + return "Country{" + + "code='" + code + '\'' + + ", name='" + name + '\'' + + ", url='" + url + '\'' + + '}'; + } +} diff --git a/java-jasper/src/main/resources/report.jrxml b/java-jasper/src/main/resources/report.jrxml new file mode 100644 index 00000000..113a787a --- /dev/null +++ b/java-jasper/src/main/resources/report.jrxml @@ -0,0 +1,37 @@ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/java-lambda/README.md b/java-lambda/README.md new file mode 100644 index 00000000..8213fe8e --- /dev/null +++ b/java-lambda/README.md @@ -0,0 +1,151 @@ +Using Lambda to Implement Functional Interface Method +==================================================== + +- We have a *virtual* `Button` that when clicked will call an abstract method **onClick()** of a listener interface `OnClickListener`. +- We need to implement the **onClick()** so that it prints the `Button` name. + +`OnClickListener.java` + +```java +package com.hmkcode; + +public interface OnClickListener { + void onClick(Button button); +} +``` + +`Button.java` + +```java +package com.hmkcode; + +public class Button { + + private OnClickListener onClickListener; + private String name; + + // click the button + public void click(){ + this.onClickListener.onClick(this); + } + + // getters & setters +} +``` + +- We have three ways to achieve that: + 1. **Implement** `OnClickListener` and override **onClick()** method. + 2. Use `OnClickListener` as an anonymous class. + 3. Use Lambda. + +- Our main class is `App.java` + +```java +package com.hmkcode; + +public class App +{ + public static void main( String[] args ){ + System.out.println( "Running App..." ); + new App().run(); + } + + public void run(){ + + Button myButton = new Button(); + myButton.setName("MyButton"); + + // 1. implements onClickListener + + // 2. anonymous class + + // 3. lambda + + + // click the button + myButton.click(); + } +} +``` + +### 1. **Implement** `OnClickListener` and override **onClick()** method + +```java +public class App implements OnClickListener +{ + public static void main( String[] args ){...} + + public void run(){ + + Button myButton = new Button(); + myButton.setName("MyButton"); + + // 1. implements onClickListener + myButton.setOnClickListener(this); + + // click the button + myButton.click(); + } + + @Override + public void onClick(Button button) { + System.out.println(button.getName() +" Clicked! - implements interface"); + + } +} +``` + +### 2. Use `OnClickListener` as an anonymous class + +```java +public class App +{ + public static void main( String[] args ){...} + + public void run(){ + + Button myButton = new Button(); + myButton.setName("MyButton"); + + // 2. anonymous class + myButton.setOnClickListener(new OnClickListener() { + @Override + public void onClick(Button button) { + System.out.println(button.getName() +" Clicked! - anonymous class"); + } + }); + + // click the button + myButton.click(); + } +} +``` + +### 3. Use Lambda + +```java +public class App +{ + public static void main( String[] args ){...} + + public void run(){ + + Button myButton = new Button(); + myButton.setName("MyButton"); + + // 3. lambda + OnClickListener lambda = button -> { System.out.println(button.getName()+" Clicked! - lambda"); } ; + myButton.setOnClickListener(lambda); + + // click the button + myButton.click(); + } +} +``` + +*To run the code use* + +``` +java-lambda>mvn exec:java +``` + diff --git a/java-lambda/pom.xml b/java-lambda/pom.xml new file mode 100644 index 00000000..8240ec70 --- /dev/null +++ b/java-lambda/pom.xml @@ -0,0 +1,34 @@ + + + + 4.0.0 + + com.hmkcode + java-lambda + 1.0-SNAPSHOT + + java-lambda + + + + + maven-compiler-plugin + 3.8.0 + + 1.8 + 1.8 + + + + org.codehaus.mojo + exec-maven-plugin + 1.6.0 + + com.hmkcode.App + + + + + + diff --git a/java-lambda/src/main/java/com/hmkcode/App.java b/java-lambda/src/main/java/com/hmkcode/App.java new file mode 100644 index 00000000..c1cdd001 --- /dev/null +++ b/java-lambda/src/main/java/com/hmkcode/App.java @@ -0,0 +1,42 @@ +package com.hmkcode; + + +public class App implements OnClickListener +{ + public static void main( String[] args ){ + System.out.println( "Running App..." ); + new App().run(); + } + + public void run(){ + + Button myButton = new Button(); + myButton.setName("MyButton"); + + // 1. implements onClickListener + //myButton.setOnClickListener(this); + + // 2. anonymous class + /*myButton.setOnClickListener(new OnClickListener() { + @Override + public void onClick(Button button) { + System.out.println(button.getName() +" Clicked! - anonymous class"); + } + }); */ + + // 3. lambda + OnClickListener lambda = button -> { System.out.println(button.getName()+" Clicked! - lambda"); } ; + myButton.setOnClickListener(lambda); + + + // click the button + myButton.click(); + } + + + @Override + public void onClick(Button button) { + System.out.println(button.getName() +" Clicked! - implements interface"); + + } +} diff --git a/java-lambda/src/main/java/com/hmkcode/Button.java b/java-lambda/src/main/java/com/hmkcode/Button.java new file mode 100644 index 00000000..adc65baf --- /dev/null +++ b/java-lambda/src/main/java/com/hmkcode/Button.java @@ -0,0 +1,31 @@ +package com.hmkcode; + +public class Button { + + private OnClickListener onClickListener; + private String name; + + public void click(){ + this.onClickListener.onClick(this); + } + + + public String getName() { + return name; + } + + public void setName(String name) { + this.name = name; + } + + public OnClickListener getOnClickListener() { + return onClickListener; + } + + public void setOnClickListener(OnClickListener onClickListener) { + this.onClickListener = onClickListener; + } + + + +} diff --git a/java-lambda/src/main/java/com/hmkcode/OnClickListener.java b/java-lambda/src/main/java/com/hmkcode/OnClickListener.java new file mode 100644 index 00000000..662f65c7 --- /dev/null +++ b/java-lambda/src/main/java/com/hmkcode/OnClickListener.java @@ -0,0 +1,7 @@ +package com.hmkcode; + + +public interface OnClickListener { + void onClick(Button button); + +} diff --git a/java-servlet-json/.classpath b/java-servlet-json/.classpath index fd0d555d..3579da99 100644 --- a/java-servlet-json/.classpath +++ b/java-servlet-json/.classpath @@ -1,11 +1,10 @@ - - - - + + + \ No newline at end of file diff --git a/java-servlet-json/pom.xml b/java-servlet-json/pom.xml index dd7dc447..f37f61f0 100644 --- a/java-servlet-json/pom.xml +++ b/java-servlet-json/pom.xml @@ -5,7 +5,7 @@ com.hmkcode java-servlet-json 1.0-SNAPSHOT - jar + war java-servlet-json http://maven.apache.org @@ -15,36 +15,39 @@ - + javax.servlet javax.servlet-api 3.1.0 + provided + + com.fasterxml.jackson.core jackson-core - 2.2.2 + 2.9.6 com.fasterxml.jackson.core jackson-databind - 2.2.2 + 2.9.6 com.fasterxml.jackson.core jackson-annotations - 2.2.2 + 2.9.6 java-servlet-json - - org.eclipse.jetty + + org.eclipse.jetty jetty-maven-plugin - 9.0.4.v20130625 - + 9.4.11.v20180605 + diff --git a/java-servlet-json/src/main/java/com/hmkcode/JSONServlet.java b/java-servlet-json/src/main/java/com/hmkcode/JSONServlet.java index afccf9b4..67415b87 100644 --- a/java-servlet-json/src/main/java/com/hmkcode/JSONServlet.java +++ b/java-servlet-json/src/main/java/com/hmkcode/JSONServlet.java @@ -6,6 +6,7 @@ import java.util.LinkedList; import java.util.List; import javax.servlet.ServletException; +import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @@ -13,6 +14,7 @@ import com.fasterxml.jackson.databind.ObjectMapper; import com.hmkcode.vo.Article; +@WebServlet("/jsonservlet") public class JSONServlet extends HttpServlet { private static final long serialVersionUID = 1L; @@ -32,21 +34,22 @@ protected void doPost(HttpServletRequest request, HttpServletResponse response) String json = ""; if(br != null){ json = br.readLine(); + System.out.println(json); } // 2. initiate jackson mapper - ObjectMapper mapper = new ObjectMapper(); + ObjectMapper mapper = new ObjectMapper(); - // 3. Convert received JSON to Article - Article article = mapper.readValue(json, Article.class); + // 3. Convert received JSON to Article + Article article = mapper.readValue(json, Article.class); // 4. Set response type to JSON response.setContentType("application/json"); - // 5. Add article to List

+ // 5. Add article to List

articles.add(article); // 6. Send List

as JSON to client - mapper.writeValue(response.getOutputStream(), articles); + mapper.writeValue(response.getOutputStream(), articles); } } diff --git a/java-servlet-json/src/main/webapp/WEB-INF/web.xml b/java-servlet-json/src/main/webapp/WEB-INF/web.xml deleted file mode 100644 index ac732e11..00000000 --- a/java-servlet-json/src/main/webapp/WEB-INF/web.xml +++ /dev/null @@ -1,20 +0,0 @@ - - - Java Servlet JSON - - index.html - - - - jsonservlet - com.hmkcode.JSONServlet - - - jsonservlet - /jsonservlet - - \ No newline at end of file diff --git a/java-spi/java-spi-api/pom.xml b/java-spi/java-spi-api/pom.xml new file mode 100644 index 00000000..e7c1e87d --- /dev/null +++ b/java-spi/java-spi-api/pom.xml @@ -0,0 +1,27 @@ + + + + 4.0.0 + + com.hmkcode.api + java-spi-api + 1.0-SNAPSHOT + + java-spi-api + + http://www.example.com + + + UTF-8 + 1.7 + 1.7 + + + + + + + + + diff --git a/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyService.java b/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyService.java new file mode 100644 index 00000000..4928f453 --- /dev/null +++ b/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyService.java @@ -0,0 +1,6 @@ +package com.hmkcode.api; + +public interface MyService { + + void doSomething(); +} diff --git a/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyServiceProviderInterface.java b/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyServiceProviderInterface.java new file mode 100644 index 00000000..8e166424 --- /dev/null +++ b/java-spi/java-spi-api/src/main/java/com/hmkcode/api/MyServiceProviderInterface.java @@ -0,0 +1,6 @@ +package com.hmkcode.api; + +public interface MyServiceProviderInterface { + + MyService getService(); +} diff --git a/java-spi/java-spi-app/lib/java-spi-api-1.0-SNAPSHOT.jar b/java-spi/java-spi-app/lib/java-spi-api-1.0-SNAPSHOT.jar new file mode 100644 index 00000000..23a1c6be Binary files /dev/null and b/java-spi/java-spi-app/lib/java-spi-api-1.0-SNAPSHOT.jar differ diff --git a/java-spi/java-spi-app/lib/java-spi-impl1-1.0-SNAPSHOT.jar b/java-spi/java-spi-app/lib/java-spi-impl1-1.0-SNAPSHOT.jar new file mode 100644 index 00000000..c8007874 Binary files /dev/null and b/java-spi/java-spi-app/lib/java-spi-impl1-1.0-SNAPSHOT.jar differ diff --git a/java-spi/java-spi-app/pom.xml b/java-spi/java-spi-app/pom.xml new file mode 100644 index 00000000..74906a4f --- /dev/null +++ b/java-spi/java-spi-app/pom.xml @@ -0,0 +1,40 @@ + + + + 4.0.0 + + com.hmkcode.app + java-spi-app + 1.0-SNAPSHOT + + java-spi-app + + http://www.example.com + + + UTF-8 + 1.7 + 1.7 + + + + + + com.hmkcode.api + java-spi-api + 1.0-SNAPSHOT + system + ${project.basedir}/lib/java-spi-api-1.0-SNAPSHOT.jar + + + com.hmkcode.impl + java-spi-impl1 + 1.0-SNAPSHOT + system + ${project.basedir}/lib/java-spi-impl1-1.0-SNAPSHOT.jar + + + + + diff --git a/java-spi/java-spi-app/src/main/java/com/hmkcode/app/App.java b/java-spi/java-spi-app/src/main/java/com/hmkcode/app/App.java new file mode 100644 index 00000000..8e46d684 --- /dev/null +++ b/java-spi/java-spi-app/src/main/java/com/hmkcode/app/App.java @@ -0,0 +1,9 @@ +package com.hmkcode.app; + +public class App +{ + public static void main( String[] args ) + { + MyServiceLoader.defaultProvider().getService().doSomething(); + } +} diff --git a/java-spi/java-spi-app/src/main/java/com/hmkcode/app/MyServiceLoader.java b/java-spi/java-spi-app/src/main/java/com/hmkcode/app/MyServiceLoader.java new file mode 100644 index 00000000..2efc5d74 --- /dev/null +++ b/java-spi/java-spi-app/src/main/java/com/hmkcode/app/MyServiceLoader.java @@ -0,0 +1,31 @@ +package com.hmkcode.app; + +import java.nio.file.ProviderNotFoundException; +import java.util.Iterator; +import java.util.ServiceLoader; + +import com.hmkcode.api.MyServiceProviderInterface; + + +public class MyServiceLoader { + + private static final String DEFAULT_PROVIDER = "com.hmkcode.impl.MyServiceProviderImpl1"; + + public static MyServiceProviderInterface defaultProvider() { + return provider(DEFAULT_PROVIDER); + } + + public static MyServiceProviderInterface provider(String providerName) { + ServiceLoader loader = ServiceLoader.load(MyServiceProviderInterface.class); + + Iterator it = loader.iterator(); + while (it.hasNext()) { + MyServiceProviderInterface provider = it.next(); + if (providerName.equals(provider.getClass().getName())) { + return provider; + } + } + throw new ProviderNotFoundException("provider " + providerName + " not found"); + } + +} diff --git a/java-spi/java-spi-impl1/lib/java-spi-api-1.0-SNAPSHOT.jar b/java-spi/java-spi-impl1/lib/java-spi-api-1.0-SNAPSHOT.jar new file mode 100644 index 00000000..23a1c6be Binary files /dev/null and b/java-spi/java-spi-impl1/lib/java-spi-api-1.0-SNAPSHOT.jar differ diff --git a/java-spi/java-spi-impl1/pom.xml b/java-spi/java-spi-impl1/pom.xml new file mode 100644 index 00000000..2e234c96 --- /dev/null +++ b/java-spi/java-spi-impl1/pom.xml @@ -0,0 +1,31 @@ + + + + 4.0.0 + + com.hmkcode.impl + java-spi-impl1 + 1.0-SNAPSHOT + + java-spi-impl1 + + http://www.example.com + + + UTF-8 + 1.7 + 1.7 + + + + + com.hmkcode.api + java-spi-api + 1.0-SNAPSHOT + system + ${project.basedir}/lib/java-spi-api-1.0-SNAPSHOT.jar + + + + diff --git a/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceImpl1.java b/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceImpl1.java new file mode 100644 index 00000000..24afcfa4 --- /dev/null +++ b/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceImpl1.java @@ -0,0 +1,12 @@ +package com.hmkcode.impl; + +import com.hmkcode.api.MyService; + +public class MyServiceImpl1 implements MyService{ + + @Override + public void doSomething() { + System.out.println("MyServiceImpl1"); + + } +} diff --git a/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceProviderImpl1.java b/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceProviderImpl1.java new file mode 100644 index 00000000..252b7a3e --- /dev/null +++ b/java-spi/java-spi-impl1/src/main/java/com/hmkcode/impl/MyServiceProviderImpl1.java @@ -0,0 +1,13 @@ +package com.hmkcode.impl; + +import com.hmkcode.api.MyService; +import com.hmkcode.api.MyServiceProviderInterface; + +public class MyServiceProviderImpl1 implements MyServiceProviderInterface { + + @Override + public MyService getService() { + return new MyServiceImpl1(); + } + +} diff --git a/java-spi/java-spi-impl1/src/main/resources/META-INF/services/com.hmkcode.api.MyServiceProviderInterface b/java-spi/java-spi-impl1/src/main/resources/META-INF/services/com.hmkcode.api.MyServiceProviderInterface new file mode 100644 index 00000000..008c8c11 --- /dev/null +++ b/java-spi/java-spi-impl1/src/main/resources/META-INF/services/com.hmkcode.api.MyServiceProviderInterface @@ -0,0 +1 @@ +com.hmkcode.impl.MyServiceProviderImpl1 \ No newline at end of file diff --git a/java-stream/src/main/java/com/hmkcode/App.java b/java-stream/src/main/java/com/hmkcode/App.java new file mode 100644 index 00000000..b97bbd63 --- /dev/null +++ b/java-stream/src/main/java/com/hmkcode/App.java @@ -0,0 +1,87 @@ +package com.hmkcode; + +import java.util.Arrays; +import java.util.LinkedList; +import java.util.List; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +public class App +{ + public static void main( String[] args ) + { + String[] arr = new String[]{"a", "b", "c", "d"}; + Stream stream = Arrays.stream(arr); + + stream = Stream.of("a", "b", "c", "d"); + + List list = new LinkedList(); + list.add("a"); + list.add("b"); + stream = list.stream(); + + // forEach() + stream = Stream.of("a", "b", "c", "d"); + stream.forEach(e -> System.out.println(e)); + + // distinct() | count() + stream = Stream.of("a", "b", "c", "d"); + System.out.println(stream.distinct().count()); + + // anyMatch() + stream = Stream.of("a", "b", "c", "d"); + System.out.println(stream.anyMatch(e -> e.contains("a"))); + + // filter() + stream = Stream.of("a", "b", "c", "d"); + stream.filter(e -> e.contains("b")).forEach(e -> System.out.println(e)); + + // map() + stream = Stream.of("a", "b", "c", "d"); + stream.map(e -> e.toUpperCase()).forEach(e -> System.out.println(e)); + + // flatMap() + stream = getBigList().stream().flatMap(lst -> lst.stream()); + stream.forEach(e -> System.out.println(e)); + + //[any|all|none]Match() + System.out.println(Stream.of("a", "b", "c", "d").allMatch( e -> (e.length() == 1))); + System.out.println(Stream.of("a", "b", "c", "d").noneMatch(e -> (e.length() == 2))); + System.out.println(Stream.of("a", "b", "c", "d").anyMatch( e -> e.equals("a") )); + + //reduce() + stream = Stream.of("a", "b", "c", "d"); + System.out.println(stream.reduce("", (x,y) -> apply(x,y))); + + //collect(Collectors) + stream = Stream.of("a", "b", "c", "d"); + System.out.println(stream.collect(Collectors.toList())); + + + } + + private static String apply(String a, String b){ + System.out.println(a+"->"+b); + return a+b; + } + + private static List> getBigList(){ + + List> bigList = new LinkedList>(); + + List list1 = new LinkedList(); + list1.add("a"); + list1.add("b"); + + List list2 = new LinkedList(); + list2.add("c"); + list2.add("d"); + + bigList.add(list1); + bigList.add(list2); + + return bigList; + } + + +}

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