Interface STWriter

output/java8/1.4.17/STWriter.java:42–84

Generic StringTemplate output writer filter. Literals and the elements of expressions are emitted via #write(String). Separators are emitted via #writeSeparator(String) because they must be handled specially when wrapping lines (we don't want to wrap in between an element and

public interface STWriter {
    int NO_WRAP = -1;
    void pushIndentation(String indent);
    String popIndentation();
    void pushAnchorPoint();
    void popAnchorPoint();
    void setLineWidth(int lineWidth);

    /** Write the string and return how many actual characters were written.
     *  With auto-indentation and wrapping, more chars than {@code str.length()}
     *  can be emitted.  No wrapping is done.
     */
    int write(String str) throws IOException;

    /** Same as write, but wrap lines using the indicated string as the
     *  wrap character (such as {@code "\n"}).
     */
    int write(String str, String wrap) throws IOException;

    /**
     * Because we evaluate ST instance by invoking
     * {@link Interpreter#exec(STWriter, InstanceScope)} again, we can't pass options in.
     * So the {@link Bytecode#INSTR_WRITE} instruction of an applied template
     * (such as when we wrap in between template applications like
     * {@code <data:{v|[<v>]}; wrap>}) we need to write the {@code wrap} string
     * before calling {@link Interpreter#exec}. We expose just like for the
     * separator. See {@link Interpreter#writeObject} where it checks for ST
     * instance. If POJO, {@link Interpreter#writePOJO} passes {@code wrap} to
     * {@link STWriter#write(String str, String wrap)}. Can't pass to
     * {@link Interpreter#exec}.
     */
    int writeWrap(String wrap) throws IOException;

    /** Write a separator.  Same as {@link #write(String)} except that a {@code "\n"}
     *  cannot be inserted before emitting a separator.
     */
    int writeSeparator(String str) throws IOException;

    /** Return the absolute char index into the output of the char
     *  we're about to write.  Returns 0 if no char written yet.
     */
    int index();
}