Java generating Strings with placeholders

Question

I m looking for something to achieve the following   String s    hello       s   generate s  new Object     world      assertEquals s   hello world        should be true   I could write it myself  but It seems to me that I saw a library once which did this  probably it was the slf4j logger  but i don t want to write log messages  I just want to generate strings   Do you know about a library which does this

User · Answer

This can be done in a single line without the use of library. Please check java.text.MessageFormat class.

Example

String stringWithPlaceHolder = "test String with placeholders {0} {1} {2} {3}";
String formattedStrin = java.text.MessageFormat.format(stringWithPlaceHolder, "place-holder-1", "place-holder-2", "place-holder-3", "place-holder-4");

Output will be

test String with placeholders place-holder-1 place-holder-2 place-holder-3 place-holder-4

User · Answer

Justas answer is outdated so I m posting up to date answer with apache text commons  StringSubstitutor from Apache Commons Text may be used for string formatting with named placeholders  https   commons apache org proper commons-text javadocs api-release org apache commons text StringSubstitutor html  lt dependency gt       lt groupId gt org apache commons lt  groupId gt       lt artifactId gt commons-text lt  artifactId gt       lt version gt 1 9 lt  version gt   lt  dependency gt    This class takes a piece of text and substitutes all the variables within it  The default definition of a variable is   variableName   The prefix and suffix can be changed via constructors and set methods  Variable values are typically resolved from a map  but could also be resolved from system properties  or by supplying a custom variable resolver   Example      Build map  Map lt String  String gt  valuesMap   new HashMap lt  gt      valuesMap put  quot animal quot    quot quick brown fox quot     valuesMap put  quot target quot    quot lazy dog quot     String templateString    quot The   animal  jumped over the   target   quot        Build StringSubstitutor  StringSubstitutor sub   new StringSubstitutor valuesMap        Replace  String resolvedString   sub replace templateString

User · Answer

See String format method   String s    hello  s    s   String format s   world    assertEquals s   hello world        should be true

User · Answer

There are two solutions    MessageFormat  Formatter    Formatter is more recent even though it takes over printf   which is 40 years old     Your placeholder as you currently define it is one MessageFormat can use  but why use an antique technique     Use Formatter   There is all the more reason to use Formatter that you don t need to escape single quotes  MessageFormat requires you to do so  Also  Formatter has a shortcut via String format   to generate strings  and PrintWriters have  printf    that includes System out and System err which are both PrintWriters by default

User · Answer

If you can tolerate a different kind of placeholder  i e   s in place of     you can use String format method for that   String s    hello  s    s   String format s   world     assertEquals s   hello world        true

User · Answer

StrSubstitutor from Apache Commons Lang may be used for string formatting with named placeholders    lt dependency gt       lt groupId gt org apache commons lt  groupId gt       lt artifactId gt commons-text lt  artifactId gt       lt version gt 1 1 lt  version gt   lt  dependency gt    https   commons apache org proper commons-lang javadocs api-3 4 org apache commons lang3 text StrSubstitutor html       Substitutes variables within a string by values       This class takes a piece of text and substitutes all the variables   within it  The default definition of a variable is   variableName     The prefix and suffix can be changed via constructors and set methods       Variable values are typically resolved from a map  but could also be   resolved from system properties  or by supplying a custom variable   resolver    Example   String template    Hi   name   Your number is   number     Map lt String  String gt  data   new HashMap lt String  String gt     data put  name    John    data put  number    1     String formattedString   StrSubstitutor replace template  data

User · Answer

You won t need a library  if you are using a recent version of Java  have a look at String format   String format  Hello  s     world

User · Answer

If you can change the format of your placeholder  you could use String format    If not  you could also replace it as pre-processing   String format  hello  s     world      More information in this other thread

[java] Java generating Strings with placeholders

Examples related to java

Examples related to string