Große Zeichenfolge aufgeteilt in Zeilen mit maximaler Länge in Java

Besten : Apache-Commons-Lang :

org.apache.Unterhaus.lang.WordUtils

/**
 * <p>Wraps a single line of text, identifying words by <code>' '</code>.</p>
 * 
 * <p>New lines will be separated by the system property line separator.
 * Very long words, such as URLs will <i>not</i> be wrapped.</p>
 * 
 * <p>Leading spaces on a new line are stripped.
 * Trailing spaces are not stripped.</p>
 *
 * <pre>
 * WordUtils.wrap(null, *) = null
 * WordUtils.wrap("", *) = ""
 * </pre>
 *
 * @param str  the String to be word wrapped, may be null
 * @param wrapLength  the column to wrap the words at, less than 1 is treated as 1
 * @return a line with newlines inserted, <code>null</code> if null input
 */
public static String wrap(String str, int wrapLength) {
    return wrap(str, wrapLength, null, false);
}

InformationsquelleAutor der Antwort Saad Benbouzid

Können Sie WordUtils.wrap-Methode, die der Apache Commans Lang

 import java.util.*;
 import org.apache.commons.lang3.text.WordUtils;
 public class test3 {


public static void main(String[] args) {

    String S = "THESE TERMS AND CONDITIONS OF SERVICE (the Terms) ARE A LEGAL AND BINDING AGREEMENT BETWEEN YOU AND NATIONAL GEOGRAPHIC governing your use of this site, www.nationalgeographic.com, which includes but is not limited to products, software and services offered by way of the website such as the Video Player, Uploader, and other applications that link to these Terms (the Site). Please review the Terms fully before you continue to use the Site. By using the Site, you agree to be bound by the Terms. You shall also be subject to any additional terms posted with respect to individual sections of the Site. Please review our Privacy Policy, which also governs your use of the Site, to understand our practices. If you do not agree, please discontinue using the Site. National Geographic reserves the right to change the Terms at any time without prior notice. Your continued access or use of the Site after such changes indicates your acceptance of the Terms as modified. It is your responsibility to review the Terms regularly. The Terms were last updated on 18 July 2011.";
    String F = WordUtils.wrap(S, 20);
    String[] F1 =  F.split(System.lineSeparator());
    System.out.println(Arrays.toString(F1));

}}

Ausgabe

   [THESE TERMS AND, CONDITIONS OF, SERVICE (the Terms), ARE A LEGAL AND, BINDING AGREEMENT, BETWEEN YOU AND, NATIONAL GEOGRAPHIC, governing your use, of this site,, www.nationalgeographic.com,, which includes but, is not limited to, products, software, and services offered, by way of the, website such as the, Video Player,, Uploader, and other, applications that, link to these Terms, (the Site). Please, review the Terms, fully before you, continue to use the, Site. By using the, Site, you agree to, be bound by the, Terms. You shall, also be subject to, any additional terms, posted with respect, to individual, sections of the, Site. Please review, our Privacy Policy,, which also governs, your use of the, Site, to understand, our practices. If, you do not agree,, please discontinue, using the Site., National Geographic, reserves the right, to change the Terms, at any time without, prior notice. Your, continued access or, use of the Site, after such changes, indicates your, acceptance of the, Terms as modified., It is your, responsibility to, review the Terms, regularly. The Terms, were last updated on, 18 July 2011.]

InformationsquelleAutor der Antwort Ravichandra

Ich habe vor kurzem geschrieben, ein paar Methoden, dies zu tun, dass, wenn keine Leerzeichen vorhanden sind, in eine der Linien, entscheidet sich für die Aufteilung auf andere nicht-alphanumerische Zeichen vor Rückgriff auf eine Mitte-word aufgeteilt.

Hier ist, wie es stellte sich für mich heraus:

(Verwendet die lastIndexOfRegex() Methoden, die ich gepostet hier.)

/**
 * Indicates that a String search operation yielded no results.
 */
public static final int NOT_FOUND = -1;



/**
 * Version of lastIndexOf that uses regular expressions for searching.
 * By Tomer Godinger.
 * 
 * @param str String in which to search for the pattern.
 * @param toFind Pattern to locate.
 * @return The index of the requested pattern, if found; NOT_FOUND (-1) otherwise.
 */
public static int lastIndexOfRegex(String str, String toFind)
{
    Pattern pattern = Pattern.compile(toFind);
    Matcher matcher = pattern.matcher(str);

    //Default to the NOT_FOUND constant
    int lastIndex = NOT_FOUND;

    //Search for the given pattern
    while (matcher.find())
    {
        lastIndex = matcher.start();
    }

    return lastIndex;
}

/**
 * Finds the last index of the given regular expression pattern in the given string,
 * starting from the given index (and conceptually going backwards).
 * By Tomer Godinger.
 * 
 * @param str String in which to search for the pattern.
 * @param toFind Pattern to locate.
 * @param fromIndex Maximum allowed index.
 * @return The index of the requested pattern, if found; NOT_FOUND (-1) otherwise.
 */
public static int lastIndexOfRegex(String str, String toFind, int fromIndex)
{
    //Limit the search by searching on a suitable substring
    return lastIndexOfRegex(str.substring(0, fromIndex), toFind);
}

/**
 * Breaks the given string into lines as best possible, each of which no longer than
 * <code>maxLength</code> characters.
 * By Tomer Godinger.
 * 
 * @param str The string to break into lines.
 * @param maxLength Maximum length of each line.
 * @param newLineString The string to use for line breaking.
 * @return The resulting multi-line string.
 */
public static String breakStringToLines(String str, int maxLength, String newLineString)
{
    StringBuilder result = new StringBuilder();
    while (str.length() > maxLength)
    {
        //Attempt to break on whitespace first,
        int breakingIndex = lastIndexOfRegex(str, "\\s", maxLength);

        //Then on other non-alphanumeric characters,
        if (breakingIndex == NOT_FOUND) breakingIndex = lastIndexOfRegex(str, "[^a-zA-Z0-9]", maxLength);

        //And if all else fails, break in the middle of the word
        if (breakingIndex == NOT_FOUND) breakingIndex = maxLength;

        //Append each prepared line to the builder
        result.append(str.substring(0, breakingIndex + 1));
        result.append(newLineString);

        //And start the next line
        str = str.substring(breakingIndex + 1);
    }

    //Check if there are any residual characters left
    if (str.length() > 0)
    {
        result.append(str);
    }

    //Return the resulting string
    return result.toString();
}

InformationsquelleAutor der Antwort Tomer Godinger

Seit Java 8 Sie können auch Streams zur Bewältigung solcher Probleme.

Folgenden finden Sie ein vollständiges Beispiel, nutzt Reduzierung mit der .collect () - Methode

Ich denke, das sollte kürzer sein als andere, nicht-3rd-party-Lösungen.

private static String multiLine(String longString, String splitter, int maxLength) {
    return Arrays.stream(longString.split(splitter))
            .collect(
                ArrayList<String>::new,     
                (l, s) -> {
                    Function<ArrayList<String>, Integer> id = list -> list.size() - 1;
                    if(l.size() == 0 || (l.get(id.apply(l)).length() != 0 && l.get(id.apply(l)).length() + s.length() >= maxLength)) l.add("");
                    l.set(id.apply(l), l.get(id.apply(l)) + (l.get(id.apply(l)).length() == 0 ? "" : splitter) + s);
                },
                (l1, l2) -> l1.addAll(l2))
            .stream().reduce((s1, s2) -> s1 + "\n" + s2).get();
}

public static void main(String[] args) {
    String longString = "THESE TERMS AND CONDITIONS OF SERVICE (the Terms) ARE A LEGAL AND BINDING AGREEMENT BETWEEN YOU AND NATIONAL GEOGRAPHIC governing your use of this site, www.nationalgeographic.com, which includes but is not limited to products, software and services offered by way of the website such as the Video Player, Uploader, and other applications that link to these Terms (the Site). Please review the Terms fully before you continue to use the Site. By using the Site, you agree to be bound by the Terms. You shall also be subject to any additional terms posted with respect to individual sections of the Site. Please review our Privacy Policy, which also governs your use of the Site, to understand our practices. If you do not agree, please discontinue using the Site. National Geographic reserves the right to change the Terms at any time without prior notice. Your continued access or use of the Site after such changes indicates your acceptance of the Terms as modified. It is your responsibility to review the Terms regularly. The Terms were last updated on 18 July 2011.";
    String SPLITTER = " ";
    int MAX_LENGTH = 20;
    System.out.println(multiLine(longString, SPLITTER, MAX_LENGTH));
}

InformationsquelleAutor der Antwort Markus Weninger