This is a sample Rmarkdown-Shiny file that crashes every second time a ggplot/lattice object is rendered, without throwing an error. This problem seems to happen only when a package that uses java is imported. (RJava does not cause any problems)

TestRmarkdownShiny.Rmd

---
title: "TestMarkdownShiny"
author: "Ashwin Raaghav"
date: "30 August 2017"
output: html_document
runtime: shiny
---

This R Markdown document is made to test the functioning of **renderplot** rendering a **ggplot** when a library that uses ***rJava*** is imported into the session. 

The second time the ggplot plot is rendered, it crashes the document itself, without throwing any error.

```{r version}
version
```


## Shiny - Ggplot2 - Rjava test


```{r Shiny renderplot Ggplot2 Rjava test, echo=FALSE, results='asis', warning=FALSE, error=FALSE}

## rJava based libraries cause a problem.
library(openNLP)
library(wordnet)
library(openNLPmodels.en)
library(RWeka)
library(Rdrools)

## Interestingly enough, rJava does not cause a problem....
# library(rJava)

library(shiny)

library(ggplot2)
library(lattice)

renderText("Now we see how it works...")

inputPanel(
  actionButton('submit', 'Click twice to crash')
)

uiOutput('ggOut')

observeEvent(input$submit, {
  
  df <- data.frame('words' = LETTERS[1:20], 'number' = round(runif(20, 0, 100)), stringsAsFactors = FALSE)
  
  output$ggOut <- renderUI({
    list(
      renderPlot({  ## ggplot (Doesnt work)
        ggplot(df, aes(x = words, y = number)) + geom_bar(stat = 'identity')
      }),
      renderPlot({  ## lattice (Doesnt work)
        lattice::barchart(x = number ~ words, data = df)
      }),
      renderPlot({  ## deafult graphics plot. (WORKS)
        graphics::barplot(df$number, names.arg = df$words)
      })
    )
  })
})

```