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POJava exception when adding to map
 

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  1. POJava exception when adding to map
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    <p>Not sure what is wrong...it should work or maybe am missing something? the following is the code:</p> <pre><code>public class TestOracleMap implements java.io.Serializable{ static TreeMap&lt;String, Integer&gt; map; static TreeMap&lt;String, Integer&gt; localMap = new TreeMap&lt;String, Integer&gt;(); public static void StoreMapInDB(TreeMap&lt;String, Integer&gt; map) throws IOException, FileNotFoundException{ try { PreparedStatement insertMap = null; //String insertString = "INSERT INTO TESTMAP(ID, MPFIELD) VALUES (1, ?)"; Connection con=null; con.setAutoCommit(false); Class.forName("oracle.jdbc.driver.OracleDriver"); con=DriverManager.getConnection( "jdbc:oracle:thin:@oXXX", "XXX", "XXX"); ByteArrayOutputStream bos = new ByteArrayOutputStream() ; ObjectOutputStream out = new ObjectOutputStream(bos); out = new ObjectOutputStream(bos) ; out.writeObject(map); out.close(); byte[] buf = bos.toByteArray(); PreparedStatement prepareStatement = con.prepareStatement("insert into TESTMAP(ID,MAPFIELD)values(?,?)"); prepareStatement.setLong(1, 1); prepareStatement.setBinaryStream(2, new ByteArrayInputStream(buf), buf.length); // insertMap.executeUpdate(); con.commit(); } catch(Exception e){e.printStackTrace();} } public static void main(String[] args) { try{ DateTime today = new DateTime(); int x = 1; map.put("Hello!", x); StoreMapInDB(map); }catch(IOException ioe){ System.err.print(ioe); } } } </code></pre> <p>the error is in the line in the main method that is:</p> <pre><code>map.put("Hello!", x); </code></pre> <p>it gives:</p> <pre><code>Exception in thread "main" java.lang.NullPointerException at core.smd.classes.TestOracleMap.main(TestOracleMap.java:61) Java Result: 1 </code></pre>
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    1. PO
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    1. This table or related slice is empty.
    1. PTQuestion
    1. USStan Kurilin
    1. USsys_debug
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    3. PO
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    1. COWhee did you initialize "map"? Looks null to me.
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      1. POJava exception when adding to map
      1. USduffymo
    2. CODid you init 'map' somewhere? I see only initialization of localMap...
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      1. POJava exception when adding to map
      1. USVolker
 

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