Java file read demonstration, to help people getting started.

README

@@ -6,6 +6,8 @@ See http://wiki.openstreetmap.org/wiki/PBF_Format .
 
 There is a Java and a C version of the PBF library code here.
 
+For a Java usage example, see src.java\crosby\binary\test\ReadFileExample.java
+
 C Version
 =========
 

pom.xml

@@ -26,6 +26,8 @@
 	<sourceDirectory>${basedir}/src.java</sourceDirectory>
     <outputDirectory>${basedir}/build</outputDirectory>
 
+   <resources><resource><directory>${basedir}/resources</directory></resource></resources>
+
     <plugins>
 	  <plugin>
         <groupId>org.apache.maven.plugins</groupId>

src.java/crosby/binary/test/ReadFileExample.java

@@ -0,0 +1,86 @@
+package crosby.binary.test;
+
+import crosby.binary.*;
+import crosby.binary.Osmformat.*;
+import crosby.binary.file.*;
+import java.io.*;
+import java.util.List;
+
+/**
+ * Demonstrates how to read a file. Reads sample.pbf from the resources folder
+ * and prints details about it to the standard output.
+ * 
+ * @author Michael Tandy
+ */
+public class ReadFileExample {
+
+    public static void main(String[] args) throws Exception {
+        InputStream input = ReadFileExample.class.getResourceAsStream("/sample.pbf");
+        BlockReaderAdapter brad = new TestBinaryParser();
+        new BlockInputStream(input, brad).process();
+    }
+
+    private static class TestBinaryParser extends BinaryParser {
+
+        @Override
+        protected void parseRelations(List<Relation> rels) {
+            if (!rels.isEmpty())
+                System.out.println("Got some relations to parse.");
+            Relation r = null;
+        }
+
+        @Override
+        protected void parseDense(DenseNodes nodes) {
+            long lastId=0;
+            long lastLat=0;
+            long lastLon=0;
+
+            for (int i=0 ; i<nodes.getIdCount() ; i++) {
+                lastId += nodes.getId(i);
+                lastLat += nodes.getLat(i);
+                lastLon += nodes.getLon(i);
+                System.out.printf("Dense node, ID %d @ %.6f,%.6f\n",
+                        lastId,parseLat(lastLat),parseLon(lastLon));
+            }
+        }
+
+        @Override
+        protected void parseNodes(List<Node> nodes) {
+            for (Node n : nodes) {
+                System.out.printf("Regular node, ID %d @ %.6f,%.6f\n",
+                        n.getId(),parseLat(n.getLat()),parseLon(n.getLon()));
+            }
+        }
+
+        @Override
+        protected void parseWays(List<Way> ways) {
+            for (Way w : ways) {
+                System.out.println("Way ID " + w.getId());
+                StringBuilder sb = new StringBuilder();
+                sb.append("  Nodes: ");
+                long lastRef = 0;
+                for (Long ref : w.getRefsList()) {
+                    lastRef+= ref;
+                    sb.append(lastRef).append(" ");
+                }
+                sb.append("\n  Key=value pairs: ");
+                for (int i=0 ; i<w.getKeysCount() ; i++) {
+                    sb.append(getStringById(w.getKeys(i))).append("=")
+                            .append(getStringById(w.getVals(i))).append(" ");
+                }
+                System.out.println(sb.toString());
+            }
+        }
+
+        @Override
+        protected void parse(HeaderBlock header) {
+            System.out.println("Got header block.");
+        }
+
+        public void complete() {
+            System.out.println("Complete!");
+        }
+
+    }
+
+}