allow chained IOExceptions even before Java 6

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/branches/MATH_2_0@712187 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/math/MathRuntimeException.java

@@ -17,6 +17,7 @@
 package org.apache.commons.math;
 
 import java.io.EOFException;
+import java.io.IOException;
 import java.io.PrintStream;
 import java.io.PrintWriter;
 import java.text.MessageFormat;
@@ -248,6 +249,22 @@ public class MathRuntimeException extends RuntimeException {
         };
     }
 
+    /**
+     * Constructs a new <code>IOException</code> with specified nested
+     * <code>Throwable</code> root cause.
+     * <p>This factory method allows chaining of other exceptions within an
+     * <code>IOException</code> even for Java 5. The constructor for
+     * <code>IOException</code> with a cause parameter was introduced only
+     * with Java 6.</p>
+     * @param rootCause the exception or error that caused this exception
+     * to be thrown.
+     */
+    public static IOException createIOException(final Throwable rootCause) {
+        IOException ioe = new IOException(rootCause.getLocalizedMessage());
+        ioe.initCause(rootCause);
+        return ioe;
+    }
+
     /**
      * Constructs a new <code>IllegalArgumentException</code> with specified formatted detail message.
      * Message formatting is delegated to {@link java.text.MessageFormat}.

src/java/org/apache/commons/math/ode/nonstiff/DormandPrince853StepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.io.ObjectInput;
 import java.io.ObjectOutput;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.FirstOrderDifferentialEquations;
 import org.apache.commons.math.ode.sampling.StepInterpolator;
@@ -250,7 +251,7 @@ class DormandPrince853StepInterpolator
       // save the local attributes
       finalizeStep();
     } catch (DerivativeException e) {
-      throw new IOException(e.getMessage());
+      throw MathRuntimeException.createIOException(e);
     }
     out.writeInt(currentState.length);
     for (int i = 0; i < currentState.length; ++i) {

src/java/org/apache/commons/math/ode/nonstiff/GraggBulirschStoerStepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.ObjectInput;
 import java.io.ObjectOutput;
 import java.io.IOException;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.sampling.AbstractStepInterpolator;
 import org.apache.commons.math.ode.sampling.StepInterpolator;
@@ -392,7 +393,7 @@ class GraggBulirschStoerStepInterpolator
       // we can now set the interpolated time and state
       setInterpolatedTime(t);
     } catch (DerivativeException e) {
-      throw new IOException(e.getMessage());
+      throw MathRuntimeException.createIOException(e);
     }
 
   }

src/java/org/apache/commons/math/ode/nonstiff/MultistepStepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 import java.io.ObjectInput;
 import java.io.ObjectOutput;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.sampling.AbstractStepInterpolator;
 
@@ -157,7 +158,7 @@ abstract class MultistepStepInterpolator
             // we can now set the interpolated time and state
             setInterpolatedTime(t);
         } catch (DerivativeException e) {
-            throw new IOException(e.getMessage());
+            throw MathRuntimeException.createIOException(e);
         }
 
     }

src/java/org/apache/commons/math/ode/nonstiff/RungeKuttaStepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.ObjectInput;
 import java.io.ObjectOutput;
 import java.io.IOException;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.FirstOrderDifferentialEquations;
 import org.apache.commons.math.ode.sampling.AbstractStepInterpolator;
@@ -165,7 +166,7 @@ abstract class RungeKuttaStepInterpolator
       // we can now set the interpolated time and state
       setInterpolatedTime(t);
     } catch (DerivativeException e) {
-      throw new IOException(e.getMessage());
+      throw MathRuntimeException.createIOException(e);
     }
 
   }

src/java/org/apache/commons/math/ode/sampling/AbstractStepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.ObjectInput;
 import java.io.ObjectOutput;
 import java.io.IOException;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.FirstOrderIntegrator;
 import org.apache.commons.math.ode.SecondOrderIntegrator;
@@ -369,7 +370,7 @@ public abstract class AbstractStepInterpolator
     try {
       finalizeStep();
     } catch (DerivativeException e) {
-      throw new IOException(e.getMessage());
+      throw MathRuntimeException.createIOException(e);
     }
 
   }

src/java/org/apache/commons/math/ode/sampling/DummyStepInterpolator.java

@@ -21,6 +21,7 @@ import java.io.ObjectInput;
 import java.io.ObjectOutput;
 import java.io.IOException;
 
+import org.apache.commons.math.MathRuntimeException;
 import org.apache.commons.math.ode.DerivativeException;
 import org.apache.commons.math.ode.nonstiff.EmbeddedRungeKuttaIntegrator;
 
@@ -119,7 +120,7 @@ public class DummyStepInterpolator
       // we can now set the interpolated time and state
       setInterpolatedTime(t);
     } catch (DerivativeException e) {
-      throw new IOException(e.getMessage());
+      throw MathRuntimeException.createIOException(e);
     }
 
   }

src/java/org/apache/commons/math/random/EmpiricalDistributionImpl.java

@@ -136,7 +136,7 @@ public class EmpiricalDistributionImpl implements Serializable, EmpiricalDistrib
                 // don't wrap RuntimeExceptions
                 throw rte;
             } catch (Exception e) {
-                throw new IOException(e.getMessage());
+                throw MathRuntimeException.createIOException(e);
             }
             if (sampleStats.getN() == 0) {
                 throw MathRuntimeException.createEOFException("URL {0} contains no data",
@@ -175,7 +175,7 @@ public class EmpiricalDistributionImpl implements Serializable, EmpiricalDistrib
                 // don't wrap RuntimeExceptions
                 throw rte;
             } catch (Exception e) {
-                throw new IOException(e.getMessage());
+                throw MathRuntimeException.createIOException(e);
             }
             in = new BufferedReader(new FileReader(file));
             fillBinStats(in);
@@ -376,7 +376,7 @@ public class EmpiricalDistributionImpl implements Serializable, EmpiricalDistrib
             // don't wrap RuntimeExceptions
             throw rte;
         } catch (Exception e) {
-            throw new IOException(e.getMessage());
+            throw MathRuntimeException.createIOException(e);
         }
 
         // Assign upperBounds based on bin counts

src/test/org/apache/commons/math/ode/sampling/DummyStepInterpolatorTest.java

@@ -120,7 +120,7 @@ public class DummyStepInterpolatorTest
         fail("an exception should have been thrown");
     } catch (IOException ioe) {
         // expected behavior
-        assertNull(ioe.getMessage());
+        assertEquals(0, ioe.getMessage().length());
     } catch (Exception e) {
         fail("wrong exception caught");
     }
@@ -166,7 +166,7 @@ public class DummyStepInterpolatorTest
         fail("an exception should have been thrown");
     } catch (IOException ioe) {
         // expected behavior
-        assertNull(ioe.getMessage());
+        assertEquals(0, ioe.getMessage().length());
     } catch (Exception e) {
         fail("wrong exception caught");
     }