별거 아닌데 계속 사용법을 까먹어서 기록해둡니다.
방법 (1)
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
public class Test {
public static void main(String[] args) {
try (InputStream inputStream = resource.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream))
){
StringBuilder stringBuilder = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
stringBuilder.append(line);
}
System.out.println("text = " + stringBuilder.toString());
} catch (IOException e) {
e.printStackTrace();
}
}
}방법 (2)
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
public class Test {
public static void main(String[] args) {
try ( BufferedReader reader = new BufferedReader(new InputStreamReader(resource))) {
String str = reader.lines().collect(Collectors.joining("\n"));
System.out.println("text = " + str);
} catch (IOException e) {
e.printStackTrace();
}
}
}방법 (3)
jdk 9 이상에서만 가능한 방법입니다. 유의하시기 바랍니다.
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
public class Test {
public static void main(String[] args) {
try (InputStream is = Test.class.getResourceAsStream("/throughput/book.txt")) {
// readAllBytes 은 jdk 9 이상에서만 제공합니다!
String text = new String(is.readAllBytes(), StandardCharsets.UTF_8);
System.out.println("text = " + text);
} catch (IOException e) {
e.printStackTrace();
}
}
}방법 (4)
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
try (InputStream is = Test.class.getResourceAsStream("/throughput/book.txt")) {
byte[] buffer = new byte[8912];
int readLen;
ByteArrayOutputStream os = new ByteArrayOutputStream();
while ((readLen = is.read(buffer)) >= 0) {
os.write(buffer, 0, readLen);
}
String text = "";
// jdk 10 이상
// String text = os.toString(StandardCharsets.UTF_8);
// jdk 10 이전
String text = new String(os.toByteArray(), StandardCharsets.UTF_8);
System.out.println("text = " + text);
} catch (IOException e) {
e.printStackTrace();
}
}
}방법 (5)
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
try (InputStream is = Test.class.getResourceAsStream("/throughput/book.txt");
Scanner scanner = new Scanner(is, StandardCharsets.UTF_8)) {
StringBuilder sb = new StringBuilder();
scanner.useDelimiter("\\\\n").forEachRemaining(sb::append);
System.out.println("text = " + sb);
} catch (IOException e) {
e.printStackTrace();
}
}
}방법 (6) IOUtils 사용
maven commons-io:common-io 아키텍쳐에 있습니다.
import org.apache.commons.io.IOUtils;
private String readEmailHtmlTemplate() {
try (InputStream is = resourceFile.getInputStream()){
return IOUtils.toString(is, StandardCharsets.UTF_8);
} catch (IOException e) {
log.error("error while reading text in file", e);
}
}방법 (7) Spring 유틸 : FileCopyUtils 사용
import org.springframework.util.FileSystemUtils;
private String readEmailHtmlTemplate() {
try (Reader rd
= new InputStreamReader(resourceFile.getInputStream(), StandardCharsets.UTF_8)
){
return FileCopyUtils.copyToString(rd);
} catch (IOException e) {
log.error("error while reading text in file", e);
}
}이외의 다양한 방법들
백엔드를 계속 배우고 있는 개발자입니다 😊