1 files changed, 45 insertions, 0 deletions
diff --git a/javaparser-core/src/main/java/com/github/javaparser/utils/SeparatedItemStringBuilder.java b/javaparser-core/src/main/java/com/github/javaparser/utils/SeparatedItemStringBuilder.java
new file mode 100644
index 000000000..3cef7237c
--- /dev/null
+++ b/javaparser-core/src/main/java/com/github/javaparser/utils/SeparatedItemStringBuilder.java
@@ -0,0 +1,45 @@
+package com.github.javaparser.utils;
+
+/**
+ * Builds a string containing a list of items with a prefix, a postfix, and a separator.
+ * <br/>Example: (1,2,3) which has prefix "(", separator ",", postfix ")" and the items 1 through 3.
+ * <p/>Java 8 offers the very nice Collectors.joining(String, String, String) which does the same thing.
+ */
+public class SeparatedItemStringBuilder {
+    private final String separator;
+    private final String postfix;
+    private boolean hasItems = false;
+    private StringBuilder builder;
+
+    public SeparatedItemStringBuilder(String prefix, String separator, String postfix) {
+        builder = new StringBuilder(prefix);
+        this.separator = separator;
+        this.postfix = postfix;
+
+    }
+
+    /**
+     * Add one item. Either pass a string, or a format for String.format and corresponding arguments.
+     */
+    public SeparatedItemStringBuilder append(CharSequence format, Object... args) {
+        if (hasItems) {
+            builder.append(separator);
+        }
+        builder.append(String.format(format.toString(), args));
+        hasItems = true;
+        return this;
+    }
+
+    public boolean hasItems() {
+        return hasItems;
+    }
+
+    /**
+     * Convert the builder into its final string representation.
+     */
+    @Override
+    public String toString() {
+        // This order of toStringing avoids debuggers from making a mess.
+        return builder.toString() + postfix;
+    }
+}