Java generating Strings with placeholders

java string named placeholder
java string format
java string placeholder substitution
java string multiple placeholder
java string format {0}
java string template literal
java sprintf
java string format multiple arguments

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?


See String.format method.

String s = "hello %s!";
s = String.format(s, "world");
assertEquals(s, "hello world!"); // should be true

A Clarified String Formatting Cheatsheet, Mulitple Placeholders. More than one placeholder can be replaced at a time. In the following example, the formatted String consists of a String� - [Instructor] String interpolation is the process … of evaluating a string literal … containing one or more placeholders. … In Java, you can do this with a method of the string class … named Format. … In this code, I have four different variables, … three strings and one numeric value. …


StrSubstitutor from Apache Commons Lang may be used for string formatting with named placeholders:

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-text</artifactId>
    <version>1.1</version>
</dependency>

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<String, String> data = new HashMap<String, String>();
data.put("name", "John");
data.put("number", "1");

String formattedString = StrSubstitutor.replace(template, data);

Java String formatting with the String.format method (like 'sprintf , The %d symbol is a placeholder that indicates that a decimal value (something like an int or long in Java) should be printed in place of this� Named placeholders filling and extraction in Java. Here's utility class that is capable of filling strings with placeholders and extract values of placeholders from filled strings. Placeholders are enclosed in % characters or curly braces. Each placeholder has a pattern, which matches any value, that this placeholder can hold.


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.

Guide to java.util.Formatter, Introduction to formatting Strings in Java using the java.util. This method accepts a template String and a list of arguments to populate the template Let's create a StringBuilder instance sb, and create a Formatter using it. Java generating Strings with placeholders. Ask Question Asked 7 years, 1 month ago. Active 7 months ago. Viewed 107k times 48. 4. I'm looking for something to achieve


Formatting Numeric Print Output (The Java™ Tutorials > Learning , Earlier you saw the use of the print and println methods for printing strings to standard output ( System.out ). The java.io package includes a PrintStream class that has two formatting Using String.format to create strings is covered in Strings. grouping separator, and the period is a placeholder for the decimal separator. This lets you store the string in one place in one format and then at a later time replace the corresponding items using only one function. That is to my knowledge not possible to do with es6 template literals. A usage for this would e.g. be translation strings where you will consume the string elsewhere and inject the desired values there.


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");

MessageFormat (Java Platform SE 7 ), Note: MessageFormat differs from the other Format classes in that you create a Within a String, a pair of single quotes can be used to quote any arbitrary� String.Format (" {0} {1}", firstNameVariable, lastNameVariable); This will return a string where the value of firstNameVariable replaces the {0} placeholder and the value of lastNameVariable replaces the {1} placeholder. This works nicely and gives you control over the resulting string.


Java String format() with examples, The java string format() method returns a formatted string using the given locale, specified format string and arguments.We can concatenate the� Apache FreeMarker™ is a template engine: a Java library to generate text output (HTML web pages, e-mails, configuration files, source code, etc.) based on templates and changing data. Templates are written in the FreeMarker Template Language (FTL), which is a simple, specialized language. You can use StringTemplateLoader to load template


Complete Printf for Java Format String Specification, The conversion type not only indicates the type of string generated from the input, but also the type of input required. Example: The format specifier " %o " means� Through different implementation methods we were able to generate bound and unbound strings, using plain Java, a Java 8 variant or the Apache Commons Library. In these Java examples, we've used java.util.Random, but one point worth mentioning is that it is not cryptographically secure.


Named placeholders filling and extraction in Java, Here's utility class that is capable of filling strings with placeholders and extract values String should match pattern used to create this object. “Formatting strings”, If you need to format your strings using String.format(String, Object…), then you can do so by putting your format arguments in the string resource. For example, with the following resource: